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The Ultimate Guide To Platelet-Rich Plasma Therapy (PRP)

In the last decade, thousands of dermatologists have started offering platelet-rich plasma (PRP) therapy as a treatment for hair loss. At first glance, PRP seems like an enticing therapy: a hands-free, drug-free approach to improve our hair thinning…

…but with a $1,000+ price tag, is the therapy worth it? Is PRP right for all hair loss sufferers? And if platelet-rich plasma therapy does work, how much hair can we expect to regrow?

This ultimate guide to platelet-rich plasma therapy uncovers the answers. Here we’ll reveal how platelet-rich plasma therapy works, how it compares to similar therapies, and what most dermatologists don’t tell you about their PRP “before-after” photos.

We’ll also reveal how hair regrowth from PRP depends largely on your form of hair loss, whether you combine PRP with other treatments, and the type of PRP your dermatologist provides (Acell, etc.).

If you’re considering PRP as a hair loss treatment, this guide will help you determine if the costs make sense for your situation and, if so, how to select the right provider.

PRP Therapy: Highlights

• Effort. Medium (requires a few dermatology appointments, but is otherwise a hands-free therapy)
• Expectations. According to studies, regrowth can occur in as little as 3 months.
• Response rate: 80%+
• Regrowth rate: this varies depending on if PRP is done alone or alongside other therapies.
  • PRP (alone): 25-30%
    • PRP + finasteride: +1%
    • PRP + microneedling: +5%
    • PRP + minoxidil: +5%
    • PRP + microneedling + minoxidil: +5-10%
    • PRP + ACell: no studies (yet), but anecdotes suggest better results than PRP alone
• Cost. $1,000-$4,000+
• Problems. Expensive; real-world results often don’t match those of studies; similar mechanisms targeted with massaging and microneedling; results vary wildly depending on the clinic; results contingent upon continued sessions

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Key takeaways

PRP is effective for androgenic alopecia and alopecia areata, but it’s expensive and requires ongoing injections to maintain results. It works best as an adjunct treatment alongside other hair loss therapies, and while it has helped both men and women, evidence suggests that it’s less effective for females overall. If you’re going to try PRP, don’t just go to any clinic; rather, vet your cosmetic surgeon by asking them a list of questions we’ve suggested (below).

What is platelet-rich plasma therapy (PRP)?

Platelet-rich plasma therapy (PRP) is an injection-based therapy. It’s the injection of a modified version of our own blood into a tissue site – with the goal to accelerate healing, reduce scarring, and improve injury outcomes.

PRP has been used for dentistry, facial reconstruction surgery, orthopedics, sports injuries, acne scarring, and fat grafting. But in the last decade, it’s been given serious attention as a potential treatment for thinning hair.

How does PRP work?

PRP therapy is a multi-step process that involves drawing a sample of our blood, separating out its platelets, concentrating those platelets, and then re-injecting those platelets into a targeted location (like our scalp).

If you’re considering PRP, the procedure usually takes around an 30-90 minutes, and the process looks something like this:

1. Obtain blood from the patient
2. Centrifuge once – under a low speed – to separate out platelet-rich plasma from the blood
3. Remove anything that isn’t plasma
4. Centrifuge again
5. Repeat step 3
6. Mix the solution to make it uniform

Why focus on platelets?

Our blood volume contains roughly 55% plasma, 40-45% red blood cells, 6% platelets, and 1% white blood cells. Whenever our tissues incur a wound – for example, a paper cut – an inflammatory reaction begins, and our bodies will send blood to our injury site to initiate repair.

Interestingly, our platelets – which constitute just 6% of our blood volume – are responsible for a huge part of the entire repair process. Specifically, platelets do two things:

1. Platelets help clot a wound to prevent excessive bleeding
2. Platelets carry with them dozens of growth factors, all of which help to coordinate the entire healing process.

This begs the question: what if we could concentrate our platelets so that instead of sending only 6% of platelets to a wound tissue, we could send a much higher percentage? Would we see better injury outcomes? Would we see less scarring?

Well, this is exactly what platelet-rich plasma therapy does. In fact, recent advents in “centrifugation” – or the swirling, mixing, and separation of platelets from our blood – have enabled dermatologists to achieve blood platelet concentrations higher than 94%+. That’s a huge jump from the 6% typically carried within our normal blood volume.

And as of today, it seems like platelet concentrations do improve injury outcomes and scarring. Decades of studies show that, on average, if we concentrate high levels of plasma and send that plasma to an injury site, we can improve injuries, reduce scar tissue, and in doing so, maybe even regrow some hair.

How, exactly, does PRP improve hair loss?

There are several growth factors carried within plasma linked to hair growth, most notably:

• Platelet-derived growth factor
• Transforming growth factor
• Vascular endothelial growth factor
• Epidermal growth factor
• Fibroblast growth factor
• Connective tissue growth factor
• Insulin-like growth factor (IGF-1)

And when injected into balding scalp tissues, the arrival of these growth factors can do a few things:

1. They reactivate dormant hair follicles and encourage them to reenter the anagen phase, thus increasing hair counts.
2. They prevent hair follicles from entering the catagen phase or undergoing cell apoptosis (programmed cell death).
3. They help to resolve longstanding inflammation and reduce scar tissue surrounding miniaturizing hair follicles, thereby increasing the hair thickness of miniaturized hairs.
4. The promote blood vessel growth around the hair follicles to aid in hair regeneration.

Isn’t this similar to how massaging and microneedling work?

Yes. PRP’s mechanisms overlap with one of the ways by which massaging and microneedling improve hair loss: they both increase the number of growth factors in balding scalp regions. But, they do it in slightly different ways.

Massaging and microneedling first generate acute inflammation (i.e., micro-wounding), which then increases growth factors, which then helps to promote hair recovery. The order of operations is as follows:

Massaging / microneedling >> evokes micro-inflammation >> evokes platelets / growth factors >> decreases scarring proteins / increases angiogenesis >> reduces perifollicular fibrosis >> improves blood flow to miniaturizing hair follicles / increases follicle growth space >> increases hair growth

But there’s a key difference between PRP and these two therapies. With massaging and microneedling, you need to first evoke inflammation to increase growth factors to a wound site. With platelet-rich plasma, you essentially skip that first step, and instead, you simply inject platelets directly into the tissue of your choosing.

When it comes to balding scalp tissues, we can think of the mechanistic difference between these therapies as this:

Now, there is some wounding involved in PRP procedures. But that wounding / acute inflammation is a consequence to the injection of the platelets. In this way, PRP is sort of like a supercharged microneedling or massage session – only with many more platelets present.

Is platelet-rich plasma therapy effective?

This is a tricky question to answer.

If forced to give a one-word answer, then yes. Most studies on PRP show positive outcomes for hair loss. But if you’re going to invest thousands of dollars into the therapy, there are caveats of which you should be made aware.

The reality is that PRP’s effectiveness for regrowth depends on the study you reference and how you define the term, “effective”. Moreover, PRP efficacy varies greatly by:

• Hair loss type (i.e., androgenic alopecia, alopecia areata, etc.)
• Whether we combine PRP with other treatments (i.e., minoxidil, finasteride, microneedling)
• The type of PRP procedure (i.e., PRP alone, PRP + Acell, etc.).

We’ll cover all of this below.  First, we’ll start with PRP’s issues. Then, we’ll dive into PRP’s benefits (and its effects on our hair).

Cons

Problem #1: most PRP studies have a high risk of bias

Most PRP studies are conducted by dermatologists who offer PRP procedures at their clinics. That creates an incentive to achieve positive results – because those positive results might encourage patients to do the procedure at their specific clinic.

However, this problem isn’t necessarily game-ending. In fact, nearly all hair loss research contains some level of bias. For instance, despite our efforts to control for bias in our own study on the massages, technically you could argue that because this site conducted it, our results are at risk of bias, too.

In any case, there are plenty of well-controlled studies on platelet-rich plasma and hair loss. We’ve filtered for these. But if you go digging through the literature and find a PRP study with crazy results, just know that if it wasn’t included in our analysis, there’s probably a good reason why.

Problem #2: most platelet-rich plasma studies aren’t standardized

Nearly every PRP study has a different patient profile (i.e., ages and hair loss severities), methodology (i.e., injection methods, rounds, treatment regions), trial duration (i.e., three months versus two years), and hair assessment method.

For instance, here are just a few ways PRP studies have measured hair loss “improvements” (ranked from worst to best).

1. Hair tug tests (i.e., when an investigator yanks at a subject’s hair before and after treatment, then counts the number of hairs that fell out)
2. Reduction in hair fall (i.e., hair shedding collected in the shower, by patients, pre- and post- treatment)
3. Patient satisfaction scores (i.e., when a patient fills out a survey saying whether they’re happy with the treatment)
4. Independent visual assessments (i.e., when a dermatologist eyeballs photos to give their input on hair improvements)
5. Follical unit survival rates (for PRP + hair transplant studies) (i.e., how many transplanted hairs survived the transfer)
6. Hair thickness (i.e., the change in the diameter of hair shafts in a specific scalp region)
7. Terminal/vellus hair ratio (i.e., the number of thick and healthy versus thin and wispy hairs in a specific region)
8. Hair counts (i.e., when a region is marked – usually with a temporary tattoo – to count hairs before and after treatment)

To be fair, this isn’t just a problem with PRP; it’s a problem with all of hair loss research. It’s why literature reviews have a hard time drawing conclusions about most treatments – because there are rarely apples-to-apples comparisons.

But again, we’ve sorted through all the PRP studies we could find to standardize the research (as best we can) and give you ballpark assessments of regrowth rates (i.e., increases to hair count in balding regions).

Problem #3: platelet-rich plasma therapy likely requires ongoing treatments

When you look into the research on minoxidil or finasteride, studies show that within 3-12 months of quitting either drug, your hair loss will return to what it was prior to the intervention. So, how long will results hold for platelet-rich plasma after quitting?

Well, it’s unclear how long results will last after you stop doing PRP treatments, but evidence suggests that a percentage of people will start seeing their hair return to baseline after a year.

Out of all PRP studies, the one with the longest follow-up period (two years) included 20 patients. Interestingly, four of them experienced a relapse in hair loss one-year post-PRP. In fact, their androgenic alopecia progressed beyond their pre-trial hair counts by the 16-month mark. This suggests that for about 20% of people, PRP’s effects start to wane 12-18 months after the treatment.

This wouldn’t be such an issue if the procedure were cheap, but it isn’t: several therapeutic rounds of PRP cost $1,000-$4,000+. So, if you’re going to give this procedure a try, make sure you’re financially comfortable with the investment.

Problem #4: PRP might not work for every person with hair loss

Out of all the research on PRP, only two studies found that PRP was an ineffective treatment option. One study was on females with androgenic alopecia. The other study was on men with advanced androgenic alopecia (Norwood gradients 4+).

If you were to ask me why the first study failed to produce results, I would say that it was probably because (like most women with hair loss) the females in that study likely had other undiagnosed hair loss types (like telogen effluvium / hair loss related to a chronic condition).

And as far as the study on men with advanced androgenic alopecia (AGA) – we need to keep in mind that the investigation team only did two rounds of PRP injections. For what it’s worth, in all of the PRP studies which saw improvement, a minimum of three PRP injection rounds were performed. So, it’s likely that either this study didn’t do enough injections to see results, or that men with advanced AGA needed several more injections before PRP begins to repeat significant benefit.

Problem #5: most PRP studies don’t measure PRP by itself

In fact, the overwhelming majority of studies measure PRP alongside other hair loss treatments – like minoxidil, finasteride, or even a hair transplant. So, it’s important to delineate between the studies you reference when evaluating whether PRP is right for you (we’ve done this below).

This also brings up another problem: dermatologists showcasing their PRP results online often don’t tell you something important: that they’re showing you PRP results alongside drugs like minoxidil and finasteride.

This is incredibly disingenuous, and I suggest that if you’re shopping around for a PRP clinic, you call ahead and ask the doctor if the results they showcase on their website are from PRP alone. If they are, great. If they’re not, but they’re labeled to make it seem as such, then that means these dermatologists are intentionally misleading prospective patients, and they should lose your business (and their license to practice).

Pros

While we might’ve just painted a problematic picture for PRP, this isn’t the whole story. In fact, PRP is an incredibly effective treatment for hair loss under the right circumstances. This is all covered below.

Alopecia areata

PRP has shown great promise for the hair loss disorder alopecia areata. This is an autoimmune condition that leads to hair loss in patchy spots throughout the head. In some cases, it can advance to complete baldness (alopecia universalis).

In fact, studies show that PRP is very effective in treating at least 70% of alopecia areata cases. Here are some of the really promising photos (source):

Androgenic alopecia

PRP alone (no other treatments)

When looking at PRP as a standalone treatment, most studies measuring hair counts suggest that the average patient will regrow 15 hairs per square centimeter (i.e., half the size of a penny). That’s about a 25-30% regrowth rate at 3-6 month follow-ups.

Quantitatively, that’s pretty impressive. For a benchmark, most studies on finasteride show just a 10% increase in hair count over two years.

Across studies, some of the less quantitative outcomes for PRP alone (at least at the 3-6 month mark) are:

• Patients report about a 75% increase in hair quality and thickness, and a decrease in the rate of hair loss.
• Patients usually perform better on the hair pull test, meaning that when they pull on a clump of the patient’s hair, fewer hairs came out compared to control groups.
• Patients report somewhat high satisfaction with the procedure at month three of follow up

Finally, a common trend mentioned among researchers is that PRP treatment seems to be more effective for patients with less severe forms of AGA. So, if you’re in the early stages of hair loss, PRP might be a great option for you.

PRP + hair transplantation

In one study examining hair transplantation, two areas with 50 grafts each(not a lot to measure, especially for hair transplantation) were compared with or without PRP injections. The area with PRP had, on average, 46.75 units that survived compared to the non-PRP which had, on average, 41 units that survived.

While this isn’t that drastic of an increase – we have to keep in mind that transplant procedures are incredibly costly… and that means that every hair follicle unit counts.

So, if you’re considering a hair transplant, you’ve spent the finances to secure a skilled surgeon, and you still have some extra spending money you’d like to throw into improving your results – do it alongside PRP. Chances are your hair transplant survival rates will improve, as will your overall hair count.

PRP + microneedling

In this study, 30 male participants received 6 PRP injections following microneedling sessions. At the six month follow-up, the average patient had a hair density increase of about 30%. This study also noted that the most significant improvement was seen in patients with less severe AGA.

PRP + minoxidil or PRP + finasteride

In this study comparing the efficacy of PRP + minoxidil and PRP + finasteride, while both outcomes were deemed effective, the PRP + minoxidil treatment actually achieved significantly better results than the PRP + finasteride group. In fact, the PRP + minoxidil group showed five-fold better hair increases versus the PRP + finasteride group.

Now, you might read these results and think that makes no sense. Finasteride is clinically more effective than minoxidil. So, why would PRP + minoxidil outperform PRP + finasteride?

Well, the devil is in the details. For one, the sample size of each PRP subgroup was less than 15 people. So, it’s possible these differences might’ve been due to statistical noise which would’ve canceled itself out with subgroups of 150+ people.

And secondly, while a five-fold improvement might sound drastic, we’re actually dealing with the law of small numbers here. Yes, PRP + finasteride saw an additional hair count lift of 1% versus 5% for the PRP + minoxidil group. And yes, that is technically a five-fold improvement. But in all reality, that’s just a few percentage points better.

PRP + minoxidil + microneedling

In this study comparing PRP + minoxidil + microneedling versus minoxidil alone, the earlier treatment proved to be much more effective than the latter, although exact numbers were not given in this study to show this. However, we can assume that PRP + minoxidil + microneedling is probably better than PRP + minoxidil, and that PRP + minoxidil is probably better than PRP alone.

PRP + Acell

PRP + Acell is a relatively new procedure that a lot of PRP practitioners are offering now. Acell is a protein matrix derived from pig bladder (you read that right) that creates a “scaffold” for new hairs. Acell essentially offers a platform by which all of our growth factors (and hair) can cling to. It also helps to stimulate stem cell activity.

[Note: since ACell is made from pig, people allergic to pig products should notify their physicians about their allergy prior to the treatment.]

There doesn’t seem to be any studies measuring the results of PRP + Acell compared to PRP alone, so it’s hard to objectively say whether it increases the effectiveness of PRP.

Are there any risks to PRP?

At least so far, there haven’t been any severe risks reported. However, some milder symptoms have been noted during and shortly after the procedure:

• Headaches
• Pain
• Itching
• Drowsiness
• Infection (rarer)
• Scarring or calcification of the injection site (for those with a propensity toward keloid scarring) (rarer)
• Blood vessel or nerve injury (rarer)

Who’s a good candidate for PRP? Who’s a bad candidate?

Androgenic alopecia treatments vary depending on your (1) finances, (2) willingness to invest time into a therapy, and (3) comfortability with FDA-approved drugs. Compared to some of the other AGA specific treatments, like standardized scalp massages and microneedling, PRP is a pricey option. At the same time, PRP is a lot less time consuming than microneedling or massaging because you may only go into a clinic for a handful of injection rounds before you start seeing results.

You are a great candidate for PRP if you…

• Are comfortable with the financial investment and ongoing treatments
• Want to stack PRP alongside other treatments in your hair loss regimen – like microneedling, massaging, minoxidil, or finasteride
• Are going to get a hair transplant and want to optimize your outcome of the procedure
• Have early-stage to mild AGA (and relatively small areas of hair loss)
• Have alopecia areata
• Are a poor candidate / do not want to try traditional hair loss medications
• Are physically healthy in general

You are not a great candidate for PRP if you…

• Do not want to spend thousands of dollars on the procedure
• Have advanced AGA and aren’t willing to commit to several rounds (and months-to-years) of injections
• Are a female with androgenic alopecia alongside conditions like hypothyroidism (treat that first!)
• Do not want to keep reinvesting money into a procedure that might not prove effective after a year.
• Have a bleeding disorder with clotting factor deficiencies or low platelet counts
• Use blood thinners
• Have a liver disorder
• Have a recent cancer history or sepsis (blood infection)
• Are a heavy smoker, alcoholic, or illicit drug user
• Have low blood pressure or chronic user of steroids

Do PRP study results hold true in the real world?

When evaluating any hair loss therapy, it’s important to note that, sometimes, study results don’t match up to real-world results. On hair loss blogs and forums, there’s sometimes an inkling that this might be the case with PRP.

For starters, while there are positive patient stories with PRP, there are also many anecdotes of patients who tried PRP without success. This video is a perfect example. And if you dig deeper, you’ll probably find more negative than positive anecdotes.

This can be confusing – as most of the literature tends to describe PRP as seemingly beneficial. And even more troublesome, it’s also worth noting that I’ve spoken with dozens of readers who’ve tried PRP… and most of them have also reported negligible improvements.

This begs the question: is PRP that effective? And regardless of the answer, why might there be a discrepancy between studies’ results and patient reports?

What could explain the discrepancies between PRP studies and real-world results?

For starters, it’s actually unclear if there are clinical versus real-world discrepancies for PRP. For instance, it’s possible that PRP treatments might just suffer from the “Yelp effect”. This is when someone with a negative experience is far more likely to leave a public review versus someone with a positive experience.

So, PRP might just be one of those treatments that have collected negative reviews over a period of years – much like finasteride and its reports of sexual side effects.

Secondly (and this is the more important point to make), clinical research does not always depict reality. For instance, while a 25-40% increase in hair count from PRP looks great on paper, it doesn’t always translate to cosmetic results.

This tends to be a problem with even the “best” FDA-approved treatments. Just take a look at these five men who did combination treatments of minoxidil, finasteride, laser combs, and even hair transplants – and their results after one year.

I’ll save you the suspense: their final “after” photos are darkened to obscure just how minimal their hair changes are. And, for the hundreds (to thousands) of dollars each of the men spent, their hair seems more-or-less cosmetically unchanged.

(Note: that video is just one of the reasons why, for most AGA sufferers, I recommend approaches like massaging / microneedling as a baseline for any regimen. Not only do these therapies enhance other hair loss treatments, but also without their inclusion, you’re statistically likely to see no cosmetic improvements from your other treatments).

Thirdly, we just learned that without follow-up sessions, PRP results will fade for 20% of patients starting 12-18 months after their last round of injections. So, if you’re reading a review of someone who got PRP once four years ago and never saw results (or is experiencing continued hair loss) – you’ll know that it’s probably because they didn’t do enough injection rounds and they didn’t keep up with the therapy.

In any case, it’s worth noting that of the readers with whom I’ve communicated, the ones who tried PRP + Acell all reported positive results. While there aren’t yet studies validating this combination therapy, it seems to be the most promising from an anecdotal standpoint (if that means anything to you).

How to choose the right PRP practitioner

If you’re going to invest $1,000+ into platelet-rich plasma, don’t give your money to the first PRP clinic you find.

Instead, find a few clinics near you that offer the procedure and make sure they have a proven track record. That means they should have a website with PRP before-after photos.

Make a list of these clinics. Then, call each clinic and ask if their online photos are of PRP alone or of PRP + finasteride / minoxidil.

If the photos are of PRP alone, great! If they’re of PRP + multi-therapies but advertised to represent only PRP… then hang up, cross them off your list, and consider reporting them the clinic to the Better Business Bureau.

Doing this should eliminate 60-70% of providers.

Next, call the remaining providers and ask about their PRP techniques. You’ll want to find a clinic that offers 1-4+ months between injection rounds. If someone offers you a package of 10 PRP sessions spaced out as one injection round per week, that goes against the literature’s recommendations (and our understanding of wound-healing timelines) – and you should probably find another provider.

Moreover, the actual PRP product that a clinic uses will vary by volume, number of injection rounds, color, platelet count, leukocyte count, and protein content. The best PRP providers will offer double-spin centrifugation preparation with an activator like thrombin or calcium chloride. While some evidence suggests that “platelet activators” are not necessary, they also don’t seem to hurt the procedure. In any case, it’ll be good to speak with your provider about all of this – so you can get a feel of whether they can actually answer these questions. If they can’t, then cross them off your list.

Lastly, ask your remaining clinics if they offer PRP + Acell. If they do (and the costs aren’t prohibitive), then this might be a better option versus PRP alone. If they don’t, it’s not the end of the world – and chances are you’ll still see benefit from the procedure.

Following this process should leave you a few great PRP clinic options. And, as long as you’re willing to commit to injections every 4-6 months, you should see a considerable lift in hair count… especially if you’re combining platelet-rich plasma with other therapies.

Summary

Platelet-rich plasma therapy is effective for both androgenic alopecia and alopecia areata, but the procedure is cost-prohibitive and requires repeated clinic visits to see sustained results. These factors are big turnoffs for most hair loss sufferers considering PRP as a treatment option.

PRP works best as an adjunct treatment alongside other hair loss therapies. So, don’t just try PRP as the only thing to help your hair. We recommend combining it with massaging and/or microneedling, and (if you’re comfortable), FDA-approved drugs (especially minoxidil) to maximize results. And, if you can, try to find a clinic that provides PRP + Acell.

While PRP can help both male and female hair loss sufferers, preliminary evidence suggests that it’s just not as effective for females. However, this might be because of the added complexities of female AGA – and the fact that women are so frequently misdiagnosed with AGA but instead actually have hair shedding disorders related to underlying chronic conditions.

Be careful about clinic selection for PRP. For instance, the photos you’ll see on most dermatology websites offering PRP are from patients doing PRP + finasteride / minoxidil (rather than PRP alone). The equivalent would be if I advertised a before-after photo of someone doing massaging + finasteride, but decided to position the photo as if the results were only from massaging. It’s just bad business. So, be aware of this. Call all clinics to confirm the regimens of their highlighted patients.

If you’re seeing improvements from PRP, chances are you’ve already navigated through this mess to find a good provider. So, steer the course and keep us posted with your progress!

Saw palmetto for hair growth: does it stack up to finasteride?

Saw palmetto is often touted as nature’s finasteride. This herbal extract reduces levels of the hormone dihydrotestosterone (DHT). For this reason, it’s clinically demonstrated to improve hair growth in men with androgenic alopecia (AGA).

But is saw palmetto as effective as finasteride?

Not quite. In fact, a closer look into the research on saw palmetto reveals that taking this supplement also comes with risks.

That’s not to say that saw palmetto is ineffective. But if you’re going to opt for saw palmetto over finasteride, you’re going to want to weigh its benefits and risks. Specifically, you’re going to want to know how saw palmetto compares to finasteride in terms of its (1) ability to reduce DHT, (2) ability to regrow hair, and (3) reported side effects.

This Quick Win dives into the details (and answers). The bottom line: saw palmetto isn’t as powerful as finasteride, but it also comes with some upsides that may make it a better option, at leaast for certain hair loss sufferers.

Note: Quick Wins are short articles focused on answering one question about hair loss. Given their specificity, these articles are written in a more scientific tone. If you’re new to hair loss research, start with our long-form articles.

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What is saw palmetto?

Saw palmetto is a palm plant native to warm humid climates (Florida).

Saw palmetto plant

Thirty years ago, researchers discovered that certain polyphenol and lipid extracts of saw palmetto could reduce the activity of type II 5-alpha reductase – an enzyme our bodies use to make the hormone dihydrotestosterone (DHT).

DHT is the main hormone implicated in pattern hair loss, also called androgenic alopecia (AGA). And interestingly, the popular hair loss drug finasteride (Propecia®) reduces that same enzyme – type II 5-alpha reductase – to lower DHT levels and improve pattern hair loss outcomes in ~80% of men trying the drug.

Unfortunately, finasteride use is also associated with sexual side effects. This scares a lot of men away from trying the drug. It also leads many of them to wonder…

“If I use saw palmetto instead of finasteride, can I still regrow hair while also reducing my risk of side effects? After all, saw palmetto is natural, and natural often means safer.”

For starters, anything branded as “natural” isn’t always safer. Many natural supplements sold through Amazon and tested by third parties have been found to contain dangerous levels of heavy metals. Moreover, many popular natural extracts – i.e., green tea extract – have been associated with hepatic failure due to the metabolic demands these extracts can place on our livers. (For more information, see my master class).

In any case, if we’re to answer the question, “Is saw palmetto as effective as finasteride?”, we’ll need to evaluate saw palmetto versus finasteride in terms of its (1) expected hair regrowth, and (2) risk of side effects.

The rest of this Quick Win does just this.

Saw palmetto vs finasteride: hair regrowth

“Hair regrowth” is a non-specific term, and most clinical studies on pattern hair loss define this term differently:

• Reductions to hair shedding
• Improvements to anagen:telogen ratios
• Increases in non-vellus hair counts
• Global photography assessments

…the list goes on.

That’s why, whenever we’re diving in studies on hair loss, we standardize the term “hair regrowth” into two categories:

1. Response Rate. This is the percentage of people receiving treatment who see a slowing, stopping, or reversal in their hair loss. After all, simply slowing down the progression of AGA is a win for most hair loss sufferers.
2. Regrowth Rate. This is the percent change in terminal (i.e., non-vellus) hair counts before and after treatment. We use this metric because it’s best out there in terms of translation to visual improvements. Increases to vellus hair counts (i.e., small, wispy, white hairs) just don’t show up in photographs, so we don’t count those.

So, if we summarize the data on saw palmetto versus finasteride, how do these two interventions compare? (1) (2)

	Saw Palmetto (320mg)	Finasteride (1mg)
Response Rate	60%; dependent on the dose and delivery (supplement or topical)	80-90%
Regrowth Rate	0-10%; potentially higher if used alongside other therapies	10%, alongside thickening of miniaturizing hair

The key takeaway: compared to finasteride, saw palmetto has a lower response rate and regrowth rate. And when we look at the individual studies that constitute these aggregated estimations, things look a little bleak.

To date, there’s only one clinical study directly comparing saw palmetto versus finasteride for the treatment of androgenic alopecia. The investigation team randomized 100 men with androgenic alopecia into two groups. They gave one group 320mg of saw palmetto and the other group 1mg of finasteride – every day, for two years. (3)

The results? After 24 months, 68% of finasteride users saw hair regrowth, while only 38% of men taking saw palmetto saw hair regrowth. Moreover, investigators noted that in the saw palmetto group, hair regrowth only occurred in the crown (i.e., vertex), and that the magnitude of regrowth was significantly less than finasteride.

In other words, saw palmetto achieves half the response rate of finasteride, and that if regrowth does occur, it’s not nearly as impressive as what finasteride achieves.

Having said that, it’s not all bad news. That same study also demonstrated that 45/50 men in the saw palmetto group saw a stop in hair loss over the two years that they took it. So, in this one study, saw palmetto showed a response rate of 90%.

This means it’s not a complete stretch to say that most men taking 320mg of saw palmetto daily should see an improvement in their pattern hair loss. It’s just that this improvement won’t be anywhere near on-par what is achievable with finasteride.

Why isn’t saw palmetto as effective as finasteride?

This likely has to do with the ways in which saw palmetto reduces DHT, and the amount of DHT that saw palmetto reduces.

Finasteride is a synthetic azosteroid. It reduces DHT by competing with (and binding to) a coenzyme that our bodies use to make type II 5-alpha reductase – the enzyme that converts free testosterone into DHT.

Conversely, saw palmetto competitively and non-competitively inhibiting type II 5-alpha reductase, reducing the binding of DHT to androgen receptors, and increasing the conversion of DHT to a weaker metabolite called androstanediol (4).

The long-story short is that these factors, along with differences in the half lives of both finasteride and saw palmetto, lead to differences in their abilities to lower DHT.

For reference, see this graph on the DHT-reducing capabilities of both saw palmetto and finasteride, as organized by different tissue sites.

The bottom line: saw palmetto is about half as effective as finasteride because it just doesn’t reduce as much DHT.

What about side effects?

At this point, we’ve really only evaluated half of the question: is saw palmetto as effective as finasteride?

In terms of response rates and regrowth rates, the answer is no. But can saw palmetto make up for its lower efficacy by being a safer long-term supplement for hair loss sufferers?

Maybe.

Saw palmetto: risk of adverse events

Long-term clinical studies show that saw palmetto’s overall rate of side effects is just 2%. Moreover, if side effects do occur, they’re relegated more so to gastrointestinal distress than to sexual dysfunction. Even better, many studies on saw palmetto show no change in libido; some studies show improvement to sexual health (at least for men with enlarged prostates). (5) (6) (7)

Finasteride: risk of adverse events

The “Yelp effect” is a phenomenon where patrons of a business are far more likely to leave a review if their experience was negative rather than positive. Finasteride is a drug that suffers from the Yelp effect, meaning that its sexual side effects are often overstated and amplified online.

Having said that, side effects do occur. Moreover, the self-assessment questionnaires filled out by participants in large-scale clinical trials for finasteride were worded in such a way where under-reporting certain side effects were more likely than not (but that’s for another article).

In any case, finasteride use does come with a heightened risk of side effects. Depending on which study you cite, between 1% and 25% of finasteride users will report issues ranging from brain fog to depression to sexual dysfunction. (8) (9) Moreover, when side effects are reported, they seem to be of higher magnitude versus saw palmetto.

The bottom line:

• Finasteride’s side effects are likely overstated online and understated in the literature
• Compared to saw palmetto, finasteride likely leads to side effects that are (1) of higher incidence, and (2) more severe

Saw palmetto or finasteride: which one is right for you?

It depends on your risk tolerance for side effects, and whether you plan on combining saw palmetto with other treatments, therapies, or procedures to make up for its lower response rates and regrowth rates.

There’s evidence that supplemental + topical saw palmetto, alongside other ingredients, might lead to better hair loss outcomes than just supplemental saw palmetto. Moreover, combining saw palmetto with massaging, microneedling, platelet-rich plasma therapy, or other interventions might help mitigate its lower efficacy.

Having said that, making these choices will depend entirely on someone’s needs, preferences, and unique hair loss situation.

Anything else to know?

Unlike finasteride, saw palmetto isn’t standardized. Serenoa repens growing conditions, extraction methods, and manufacturing practices can all impact the composition, bioavailability, and absorption of each saw palmetto supplement. In fact, these differences might explain the variances in response rates and regrowth rates seen across saw palmetto studies.

So, if you’re looking for a more comprehensive guide on how to use saw palmetto – including recommendations for dosages, extraction practices, and combinations therapies – see our saw palmetto ultimate guide here.

The bottom line

In order to evaluate whether saw palmetto is as effective as finasteride, we need to understand how the supplement compares in terms of (1) response rates, (2) regrowth rates, and (3) risk of side effects.

Saw palmetto isn’t as effective as finasteride in terms of its response rates or regrowth rates, but it also seems to cause fewer (and less severe) side effects. Because of this, making the choice to use saw palmetto over finasteride depends entirely on someone’s risk tolerance for side effects, as well as whether they plan on combining the supplement with other treatments, therapies, or procedures to make up for its less-impressive efficacy.

	Saw Palmetto (320 mg)	Finasteride (1 mg)
Response Rate	60%; dependent on the dose and delivery (supplement or topical)	80-90%
Regrowth Rate	0-10%; potentially higher if used alongside other therapies	10%, alongside thickening of miniaturizing hair
Side Effects	2%; more relegated to gastrointestinal distress than sexual side effects	1-25%; partly psychosomatic, but more severe than saw palmetto

Otherwise, if you have any questions, please feel free to leave them in the comments section.

 

Latanoprost is a medication that was originally developed to treat glaucoma. Over the last two decades, research groups have also started testing it as a treatment for hair loss – including alopecia areata, androgenic alopecia, and telogen effluvium.

Introduction

Finasteride is one of the most commonly-prescribed medications for treatment of male pattern hair loss—also known as androgenic alopecia (AGA). But it’s also used as an off-label treatment for female pattern hair loss. Evidence suggests this medication can help regrow hair in both sexes.

But what’s the best dose of finasteride for women with AGA? Unfortunately, it’s complicated. This article sets out to evaluate the data, uncover the answers, and provide recommendations based on the current landscape of clinical research.

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What Is Finasteride?

Finasteride is a drug developed to inhibit type II 5-alpha reductase. This is an enzyme in the body that converts free testosterone in dihydrotesterone (DHT).

Essentially, finasteride lowers DHT levels by reducing the amount of type II 5-alpha reductase circulating throughout our bodies. And by taking finasteride at 0.2 to 5.0 mg daily dosages, we can often reduce total DHT levels by 70%. ^[1]https://www.ncbi.nlm.nih.gov/books/NBK513329/

Why Use a Drug To Reduce DHT?

DHT is not just a metabolite of testosterone; it’s also the primary male hormone causally associated with androgenic alopecia.

We know this because studies have shown that men who cannot produce DHT are nearly fully-protected from going bald throughout a lifetime. Furthermore, clinical studies on DHT-lowering drugs – such as finasteride – show that if DHT levels are suppressed enough, 80-90% of men can arrest the progression of their pattern hair loss and even regrow 10-20% of their lost hair. ^[2]https://pubmed.ncbi.nlm.nih.gov/29407002/ ^[3]https://www.ncbi.nlm.nih.gov/books/NBK430924/

Similarly, studies on females with androgenic alopecia have shown that finasteride can also improve their hair loss outcomes. The evidence is less robust than for men, but finasteride is something many women should consider trying in order to improve their pattern hair loss.

Finasteride for Women: What’s the Perfect Dose?

In men, the FDA has approved the use of 1mg of finasteride for pattern hair loss. However, male and female hair loss cases are not always the same. Reducing DHT levels is often of therapeutic interest to fighting AGA – and for both sexes – but some clinical evidence suggests that females might need a different dose of finasteride versus males.

How Much DHT Does Finasteride Reduce?

Finasteride has what is known as a dose-dependent, logarithmic response curve for DHT reduction. In other words: a little bit of finasteride reduces nearly as much DHT as a lot of finasteride. For an example, see this chart:

Clinical studies have demonstrated that 0.2 mg and 5.0 mg reduce nearly the same amount of finasteride: 69% versus 72%, respectively.

Because of this, a lot of people actually prefer to use lower dosages of finasteride than what is generally prescribed. This practice is also supported by clinical data. For instance, in men, 0.2mg of finasteride AGA at a statistically similar level as 1.0 mg of finasteride over the course of a year. ^[4]https://europepmc.org/article/med/15319158

But is the same true with females? Unfortunately, the data is less clear.

Finasteride for Female Pattern Hair Loss: the Clinical Evidence

The FDA approves the use of 1 mg of finasteride for male pattern hair loss.^[5]https://www.fda.gov/drugs/information-drug-class/5-alpha-reductase-inhibitor-information But the underlying causes of male and female pattern hair loss cases (androgens such as DHT) are not always the same. Furthermore, while reducing DHT levels is of therapeutic relevance in treating AGA in men and women, some clinical evidence suggests that females might need a different dose of finasteride versus males. 

What does the available research tell us? Here are a few of the key studies on finasteride for women, and their main findings (summarized in the table below).

Finasteride for Women: Key Studies

Finasteride for Women: Key Studies Takeaway

There is conflicting data regarding the efficacy of finasteride for female pattern hair loss. Some studies report improvements while others do not.

There are some key variables to consider when weighing the available evidence:

• The dose of finasteride used
• The length and frequency of treatment
• Oral administration versus a topical treatment
• Whether finasteride was used in conjunction with other drugs or therapies
• The type of hair loss in the patient groups (e.g., female pattern hair loss versus age-related thinning – and was this accurately determined?)
• Patient age, history, and status (e.g., pre-, or post-menopausal, or abnormal androgen levels)
• How the treatment was assessed (e.g., quantitative hair counting versus patient self-assessment)
• Whether the study contained appropriate controls (i.e., placebo-receiving patients, ideally matched for age, weight and medical history)
• The number of patients in the study (which affects the statistical power; was the study a case report of one patient, or a larger study with a control group?).

Interpreting research data can be difficult and confusing. such as different studies using different dosages of finasteride and for varying lengths of time, measuring different hair loss outcomes, and using different numbers and ages of patients.

The specific type of hair loss is also a crucial variable.^[19]https://pubmed.ncbi.nlm.nih.gov/30604525/  Often, studies reporting positive outcomes are based on patient self-reporting, which can be suspect and not meaningfully objective or quantitative in measuring true prevention or reversal of hair loss.

What is the best dose? Explaining the conflicting results.

Given the dose-response relationship between finasteride and DHT levels, shouldn’t 1 mg be as effective as 5 mg? Why aren’t women getting consistent regrowth across doses within these ranges?

Other discrepancies are the time for which finasteride was given. In men, 1 mg of finasteride can be effective in 6-12 months, but it is possible that women require more long-term treatment regimens.^[20]https://pubmed.ncbi.nlm.nih.gov/30604525/ Generally, success with finasteride in women has been reported in both the short- and long-term.^[21]https://pubmed.ncbi.nlm.nih.gov/12399766/

Alternatively, the difference in observed efficacies between studies may be due to patient background and the type of hair loss. Hair loss in patients suffering from PCOS or adrenarche (i.e., high levels of adrenal gland activity) likely has a clear causal link to abnormal androgen signaling (and therefore suitable for finasteride), where hair loss in post-menopausal women may be more akin to age-related hair ‘thinning’, and not linked to testosterone or DHT, which may explain why some studies find no effect with finasteride.^[22]https://pubmed.ncbi.nlm.nih.gov/10674382/^[23]https://pubmed.ncbi.nlm.nih.gov/11050579/^[24]https://pubmed.ncbi.nlm.nih.gov/12399766/

That said, finasteride is also reportedly effective in patients that are androgen-normal.20 Therefore, there needs to be more careful classification of the type of hair loss and the likely underlying mechanisms, as well as clear standardization of treatment outcome measurements. 

Conclusions

Does finasteride work for women suffering from hair loss? If so, what is the ideal dosage? 

Finasteride is most beneficial for women when their hair loss occurs alongside elevated androgen levels—much like hair loss in men.

It is likely that DHT is a major factor in a proportion of female hair loss cases. Finasteride is likely to be a beneficial part of a successful hair loss regimen in these cases. However, it is not clear that male and female pattern hair loss universally share the same underlying cause.

Finasteride may be less suitable in contexts of age-related hair thinning. Hair follicles are sensitive to all manner of different hormones and chemical signals, not just androgens such as testosterone and DHT.^[25]https://pubmed.ncbi.nlm.nih.gov/32731328/

The best dose is one that maximizes the desired benefits (prevention and reversion of hair loss) while minimizing any undesirable side effects.

Finasteride can be effective at reducing DHT even in small doses. Because of this, experimentation with low levels of finasteride may lead to results with far less exposure to chemicals. Topical treatments may also be considered to further reduce systemic side effects.

Therefore, the best dose will be patient-subjective. Prior consideration of your history, goals regarding hair loss, and experimentation with dosages is needed before you will find the ideal routine for your hair health.

Topical finasteride has emerged to meet demand for hair loss treatments that promise strong results with fewer systemic side effects than oral finasteride by concentrating action at the scalp while reducing overall drug exposure. Early studies suggest it can improve hair growth and lower scalp dihydrotestosterone (DHT) with less systemic absorption, but side effects are not eliminated, and long-term head-to-head data versus oral finasteride remain limited.

This article will cut through the “same results, fewer side effects” marketing narrative and set realistic expectations by focusing on what current clinical evidence and real-world user patterns actually support.

How Does Finasteride Work?

Finasteride is a 5-alpha reductase inhibitor, meaning that it blocks this enzyme from converting testosterone into DHT, the more potent androgen that drives miniaturization of sensitive scalp follicles in androgenic alopecia (AGA). The enzyme catalyzes this conversion in the scalp, skin, liver, and prostate. By inhibiting it, finasteride lowers both local (scalp/prostate) and circulating DHT.^[1]Zito PM, Bistas KG, Patel P, et al. Finasteride. [Updated 2024 Feb 28]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from: … Continue reading

Why Oral Finasteride is Systemic

A standard 1 mg oral dose reduces DHT by roughly 60-70%, with some studies reporting around 70% suppression at steady state, and intraprostatic DHT falls by about 90%.^[2]Caserini, M., Radicioni, M., Leuratti, C., Terragni, E., Iorizzo, M., Palmieri, R. (2016). Effects of a novel finasteride 0.25% topical solution on scalp and serum dihydrotestosterone in healthy men … Continue reading,^[3]Smith, A.B., Carson, C.C. (2009). Finasteride in the treatment of patients with benign prostatic hyperplasia: a review. Therapeutics and Clinical Risk Management. 5. 535-545. Available at: … Continue reading Because 5 alpha-reductase is expressed in multiple organs, this systemic inhibition affects DHT signaling throughout the body, not only in the scalp.  

Why Side Effects Occur

Sexual and mood-related side effects are not purely “in the mind”; they reflect altered androgen physiology in a subset of men whose tissues are more sensitive to a DHT drop, even though testosterone usually stays within the normal range or rises modestly. Reduced DHT can influence libido, erectile function, ejaculate volume, and, in some individuals, mood or energy, consistent with the hormone’s broader role beyond hair follicles.^[4]Traish, A.M. (2017). Negative Impact of Testosterone Deficiency and 5ɑ-Reductase Inhibitors Therapy on Metabolic and Sexual Function in Men. Advances in experimental medicine and biology. 1043. … Continue reading

Topical Targeting vs. Spillover

Topical finasteride aims to concentrate drug action in the scalp by delivering finasteride directly to hair follicles, potentially lowering local DHT while limiting how much drug reaches the bloodstream. However, percutaneous absorption still occurs, and pharmacokinetic studies do show measurable reductions in serum DHT with topical formulations, meaning systemic exposure is reduced compared to oral dosing, but not eliminated.^[5]Caserini, M., Radicioni, M., Leuratti, C., Terragni, E., Iorizzo, M., Palmieri, R. (2016). Effects of a novel finasteride 0.25% topical solution on scalp and serum dihydrotestosterone in healthy men … Continue reading 

What the Research Says About Topical Finasteride Side Effects

The evidence on topical finasteride’s side effect profile shows a nuanced picture – measurable systemic exposure, lower but not zero adverse event rates, and substantial variability between formulations and individuals.

Systemic Absorption

The 2021 Piraccini trial, one of the largest randomized double-blind topical finasteride studies to date, tested a 0.25% finasteride spray applied once daily over 24 weeks in 458 men.^[6]Piraccini, B.M., Blume-Peytavi, U., Scarci, F., Jansat, J.M., Falques, M., Otero, R., Tamarit, M.L., Galvan, J., Tebbs, V., Massana, E., Topical Finasteride Study Group. (2022). Efficacy and safety … Continue reading Plasma finasteride concentrations were over 100-fold lower than with oral finasteride. Serum DHT fell by 34.5% with topical use compared to 55.6% with a 1 mg oral tablet.

Caserini found that lower volumes (100-200 μL of 0.25% solution) reduced serum DHT by 24-26%, while higher volumes (300-400 μL) dropped it by 44-48%.^[7]Caserini, M., Radicioni, M., Leuratti, C., Terragni, E., Iorizzo, M., Palmieri, R. (2016). Effects of a novel finasteride 0.25% topical solution on scalp and serum dihydrotestosterone in healthy men … Continue reading Even at the lowest tested doses, scalp DHT declined by roughly 47-52%, demonstrating effective local action with more limited systemic spillover.

Other studies report a range of serum DHT suppression with topical formulations, but all confirm that absorption is lower than oral administration, not absent. One hydroxyl-propyl chitosan formulation was designed specifically to retain finasteride in the reticular dermis near hair bulbs; repeated-dose rat experiments showed no detectable plasma finasteride and no accumulation in skin, although human data remain sparse.^[8]Monti. D., Tampucci, S., Burgalassi, S., Chetoni, P., Lenzi, C., Pirone, A., Mailland, F. (2014). Topical formulations containing finasteride. Part I: in vitro permeation/penetration study and in … Continue reading 

So to summarize, topical finasteride’s systemic exposure is markedly reduced compared to oral dosing, yet reductions in circulating DHT do still occur across most formulations (in human studies), meaning that some degree of systemic exposure is virtually unavoidable.

Reported Side Effect Rates in Studies

Clinical trials have monitored sexual dysfunction, dermatological reactions, and less common systemic complaints, though sample sizes and durations limit the ability to detect rare or delayed adverse events.

Sexual Side Effects

In the 2021 Piraccini study, 2.8% of topical finasteride users reported sexual adverse events (decreased libido, erectile dysfunction, and ejaculatory dysfunction) versus 4.8% on oral finasteride and 3.3% on placebo. 

The similarity between the topical and placebo groups led some investigators to suggest that many reports may not be causally linked to the drug. However, a 2025 FDA pharmacovigilance analysis of adverse event reports (2019-2024) identified 32 cases involving topical finasteride formulations, most of which were compounded products, with complaints of erectile dysfunction, anxiety, brain fog, depression, fatigue, insomnia, decreased libido, and testicular pain.^[9]US Food and Drug Administration. (2025). FDA alerts health care providers, compounders and consumers of potential risks associated with compounded topical finasteride products. FDA. Available at: … Continue reading   What’s more, many of these symptoms reportedly persisted after discontinuation.

A separate analysis found that topical finasteride generated fewer signals for post-finasteride syndrome (PFS) – like events than oral finasteride, but erectile dysfunction remained the most consistently reported adverse event for both routes.^[10]Gupta, A.K., Talukder, M., Keene, S.A., Bamimore, M.A. (2025). Is the Safety of Finasteride Correlated With Its Route of Administration: Topical Versus Oral? A Pharmacovigilance Study With Data From … Continue reading 

Scalp Irritation and Contact Dermatitis

Local reactions are the most common topical-specific side effects. A 2018 systematic review noted reports of erythema, contact dermatitis, and scalp irritation in several studies, though serious cutaneous adverse events were absent.^[12]Lee, S.W., Juhasz, M., Mobasher, P., Ekelem, C., Mesinkovska, N.A. (2018). A Systematic Review of Topical Finasteride in the Treatment of Androgenetic Alopecia in Men and Women. Journal of Drugs in … Continue reading 

Rates of contact dermatitis ranged from 12-24% in some combination formulations (finasteride + minoxidil), though these were generally mild and did not lead to treatment discontinuation. The irritation effect likely derives from vehicle components (alcohol, propylene glycol) as well as the active drug.

Headaches, Fatigue, and Other Systemic Complaints

Less frequently, trials have documented headaches, feeling about to faint, testicular pain, increased liver enzymes, and even bed-wetting in isolated cases. The 2025 FDA alert highlighted fatigue and insomnia among the systemic complaints associated with topical formulations, reinforcing that absorption can produce effects beyond the scalp.

Trial Limitations: Duration and Sample Size

Most published trials run 12-24 weeks with cohorts of 30-135 participants per arm, which may under-detect rare events (incidence <1%) or adverse effects that emerge only after prolonged exposure. Only a handful of studies have extended beyond six months, and none approach the multi-year observation periods needed to assess phenomena such as PFS.^[13]Pereira, A.F.J.R., Coehlo, T, O. de A. (2020). Post-finasteride syndrome. Anais Brasileiros de Dermatologia. 95(3). 271-277. Available at: https://doi.org/10.1016/j.abd.2020.02.001 Recruitment through specialist dermatology centres may also select for patients more tolerant of medication, introducing survivorship bias.

How do the Side Effects Compare with Oral Finasteride?

Head-to-head data have shown that topical finasteride has a numerically lower, but not zero, incidence of systemic adverse events. In Piraccini’s trial, sexual side effects occurred in 2.8% of topical users versus 4.8% of oral users, representing an approximate halving of risk.

There are two important points often overlooked in clinical summaries, however:

• Population averages do not predict individual susceptibility: Even if 97% of topical finasteride users report no sexual side effects in a 24-week trial, that statistic offers little reassurance to someone who is biochemically sensitive to modest DHT reductions. Genetic polymorphisms in 5ɑ-reductase isoforms, androgen receptor sensitivity, and neurosteroid metabolism all vary widely, meaning that a 25% serum DHT drop can be innocuous for one man and symptomatic for another.^[14]Pereira, A.F.J.R., Coehlo, T, O. de A. (2020). Post-finasteride syndrome. Anais Brasileiros de Dermatologia. 95(3). 271-277. Available at: https://doi.org/10.1016/j.abd.2020.02.001
• Short trials may miss long-latency or persistent events: Most published studies conclude at 6 months, yet reports to the FDA and patient registries describe symptoms that onset gradually or persist long after stopping treatment. The cases flagged in the FDA alert involved adverse events that continued to persist after product discontinuation, suggesting that systemic absorption, however modest, can trigger durable changes in a subset of users. However, the exact cause of symptom persistence is not yet known.

Why Do Some People Still Get Side Effects From Topical Finasteride?

Despite the reduced systemic exposure, some people still experience sexual, mood, and systemic adverse effects. Let’s take a look at the mechanisms why.

Skin Permeability Varies Significantly Between Individuals

Human skin is not a uniform barrier. Stratum corneum thickness, lipid composition, hydration status, pH, and blood flow differ among individuals and even within scalp regions of a single person. 

In vitro permeation studies using human cadaver scalp skin show that finasteride flux ranges of 1.1-20.1 μg/cm2/h, depending on vehicle choice, a roughly 18-fold variation. Live scalp skin likely exhibits even greater heterogeneity due to sebum content, follicle density, and individual differences in dermal blood flow, all of which influence how much drug reaches the bloodstream versus remaining confined to follicular tissue.^[15]Farah, A.H., Brown, M.B., McAuley, W.J. (2020). Enhanced Follicular Delivery of Finasteride to Human Scalp Skin Using Heat and Chemical Penetration Enhancers. Pharmaceutical Research. 37(6). 112. … Continue reading

For topical finasteride to minimize systemic exposure, it needs to stay within the area of the hair follicle. Variability in penetration means some individuals absorb more systemically than others, despite using the same concentration and volume.

Vehicle Formulation Dramatically Alters Absorption

The formulation of a topical finasteride product isn’t just a minor detail; it’s one of the biggest determinants of how much of the medication actually enters the bloodstream. Not all vehicles behave the same way, and the differences can be dramatic. For example, in vitro research comparing common topical solvents on human scalp skin shows that propylene glycol (PG) and isopropyl alcohol (IPA) formulations allow far more drug to pass through the skin: roughly 62–81 µg/cm² over 24 hours. In contrast, dimethyl isosorbide (DMI), often marketed as a “low-penetration” carrier, delivered just 17.8 µg/cm² in the same timeframe.^[16]Farah, A.H., Brown, M.B., McAuley, W.J. (2020). Enhanced Follicular Delivery of Finasteride to Human Scalp Skin Using Heat and Chemical Penetration Enhancers. Pharmaceutical Research. 37(6). 112. … Continue reading That’s a 4.5-fold reduction in systemic permeation, purely from changing the solvent.

More sophisticated delivery systems behave differently still. Liposomal and niosomal gels, for example, are designed to deposit the medication deeper into hair follicles while limiting diffusion into the bloodstream. And in controlled experiments, these vesicular carriers did exactly that: liquid-state liposomes delivered 2.1–2.3% of the applied dose into the skin, compared to only 0.76% from a standard hydroalcoholic solution.^[17]Tabbakhian, M., Tavakoli, N., Jaafari, M.R., Daneshamouz, S. (2006). Enhancement of follicular delivery of finasteride by liposomes and niosomes: 1. In vitro permeation and in vivo deposition studies … Continue reading 

In other words, depending on the vehicle, the same dose of finasteride can behave like a local scalp medication or something much closer to an oral drug.

At the opposite end of the spectrum are ethosomes, ethanol-rich vesicles that dramatically increase drug penetration. In one study, finasteride ethosomes produced 7.4-times higher transdermal flux than the same drug in an aqueous solution, reaching all the way into the dermis.^[18]Rao, Y., Zheng, F., Zhang, X., Gao, J., Liang, W. (2008). In vitro Percutaneous Permeation and Skin Accumulation of Finasteride Using Vesicular Ethosomal Carriers. 9(3). 860-865. Available at: … Continue reading

This is the kind of penetration behavior that significantly raises the likelihood of systemic absorption.

The bottom line: two topical finasteride products with the same concentration can have completely different side-effect profiles, simply because the vehicles modulate how much drug gets through the skin. Hydroalcoholic sprays tend to penetrate more aggressively; liposomal or niosomal gels are usually more conservative; and individual biology, skin barrier integrity, inflammation, and sebaceous output add yet another layer of variability. This is why real-world responses to topical finasteride are so mixed, and why formulation needs to be taken as seriously as the dose itself.

Concentration and Application Volume Compounds Absorption

Higher concentrations and larger volumes increase both local scalp DHT reduction and systemic spillover. As mentioned above, Caserini’s dose-response study found that applying 100-200 μL of 0.25% finasteride reduced serum DHT by 24-26%, whereas 300-400 μL volumes reduced it by 44-48%, approaching the efficacy of oral dosing at the higher end.^[19]Caserini, M., Radicioni, M., Leuratti, C., Terragni, E., Iorizzo, M., Palmieri, R. (2016). Effects of a novel finasteride 0.25% topical solution on scalp and serum dihydrotestosterone in healthy men … Continue reading 

Users who apply larger volumes, cover a wider scalp area, or use higher-concentration formulations absorb more drug systemically, shifting the risk-benefit profile toward greater potential for side effects.

Finasteride’s Half-Life Enables Accumulation

Finasteride has a terminal half-life of 5-6 hours in young men and 8 hours in older men.^[20]Mysore, V. (2012). Finasteride and sexual side effects. Indian Dermatology Online Journal. 3(1). 62-65. Available at: https://doi.org/10.4103/2229-5178.93496 Although short, daily topical application leads to steady-state accumulation in plasma and skin tissues.

With topical dosing, measurable finasteride concentrations appear in plasma within hours and remain detectable for a full day; repeated daily application amplifies cumulative levels, particularly if absorption is higher than intended due to vehicle choice or individual skin permeability.^[21]Tai, Z., Cui, Z., Shi, X., Li, H., Chai, R., Huang, Y., Fang, Y., Jia, D., Zhu, Q., Chen, Z. (2025). The Pharmacokinetics of Topical Finasteride 0.25% Spray in Chinese Adult Male Volunteers with … Continue reading 

DHT Sensitivity Varies Widely Between Individuals

Even when two people experience the same level of DHT reduction, their bodies may not respond the same way. This is where individual biology plays a much bigger role than most clinical studies acknowledge. Variations in genes tied to 5α-reductase activity, androgen receptor sensitivity (including CAG repeat length), and enzymes involved in neurosteroid production, such as 3α-HSD, can all influence how strongly someone reacts to changes in DHT.^[22]Cecchin, E., De Mattia, E., Toffoli, G.,  Mazzon, G., Cauci, S., Trombetta, C. (2014). A Pharmacogenetic Survey of Androgen Receptor (CAG)N and (GGN)N Polymorphisms in Patients Experiencing … Continue reading,^[23]Rahimi-Ardabili, B., Pourandarjani, R., Habibollahi, P., Mualeki, A. (2006). Finasteride-induced depression: a prospective study. BMC Clinical Pharmacology. 6(7). Available at: … Continue reading 

For one man, a 30% drop in circulating DHT might feel completely benign. For another, that exact same reduction might coincide with noticeable changes in libido, erectile quality, or overall sexual function.

Layered on top of genetics are factors like baseline hormone levels, underlying hypogonadism, and even a person’s psychophysiological sensitivity to small hormonal shifts. Together, these variables help explain why side effects remain so individualized and difficult to predict, and why two people using an identical topical finasteride formulation can walk away with very different experiences. This isn’t meant to alarm anyone, only to highlight that DHT suppression is not a one-size-fits-all phenomenon, and that understanding your own sensitivity is often just as important as choosing the right dose or vehicle.

How Can I Minimize the Risk of Topical Finasteride Side Effects?

Target the Lowest Effective Exposure

• Understand exposure = concentration × volume. The systemic finasteride dose delivered through the scalp depends on both how strong the solution is and how much is applied. A low-concentration solution applied in large volume can expose the body to as much finasteride as a small volume of a stronger solution. Both variables must be considered together when aiming to reduce side effects.
• Start with the minimum viable dose. Evidence suggests that daily exposure to around 0.1 mg (for example, 0.005% solution applied at 2 mL per day) can still achieve measurable scalp DHT reduction with negligible systemic suppression.
• 0.25% remains the most studied concentration. Clinical trials show that 0.25% topical finasteride effectively treats androgenetic alopecia with hair density gains similar to oral finasteride yet significantly lower serum DHT reduction. For most users, starting at or below this level helps balance efficacy and safety.
• Higher isn’t always better. Increasing concentration or volume each raises systemic absorption, but hair-growth benefits tend to plateau. Pushing beyond the optimal concentration can shift the risk-to-benefit ratio unfavorably.
• Consider titrating upward. If highly sensitive to hormonal side effects, begin at lower exposure (e.g., 0.025–0.1% at 1 mL daily), then increase concentration or frequency only if well-tolerated and results plateau. Serum DHT measurements can help assess systemic exposure over time.

Adjust Volume and Frequency to Limit Systemic Load

• Keep volume conservative. Systemic absorption scales with total dose applied. Around 1 mL per application is a common clinical standard; using more typically provides diminishing returns for hair outcomes but notably raises systemic uptake.
• Use the lowest frequency that maintains results. Because twice-daily 0.25% use can suppress serum DHT by up to 70%—similar to oral dosing—while once-daily reduces it by only 20–35%, finding a balance between efficacy and exposure is key. For many users, once-daily application of a lower-strength solution achieves a good safety–efficacy trade-off.

Choose Vehicles Carefully

• Hydroalcoholic vs. liposomal: Standard hydroalcoholic (alcohol-based) solutions enhance drug penetration, which can lead to greater systemic absorption. In contrast, advanced vehicles like liposomal or other nanoparticle-based formulations are designed to target drug delivery to the hair follicle and reduce transdermal flux into the bloodstream.

Implement Smart Application Strategies

• Apply to a dry scalp: Applying topicals to wet skin can enhance absorption. Ensure the scalp is completely dry to create a more robust barrier.
• Target affected areas only: Use the applicator to apply the solution precisely to the areas of thinning hair, not the entire scalp, to limit the total surface area of absorption. 
• Avoid compromised barriers: Do not apply the solution immediately after microneedling, on sunburnt skin, or on a scalp with cuts, inflammation, or dermatitis, as a compromised skin barrier significantly increases uptake.
• Wash hands thoroughly: Always wash hands with soap and water after application to prevent accidental transfer to other body parts or individuals.

Important: If you experience any side effects, we recommend first stopping and speaking to your primary care physician.

Who Should Avoid or Be Cautious with Topical Finasteride?

While topical finasteride carries a lower risk profile than its oral counterpart, some people may still need to exercise caution or avoid the drug entirely. 

Groups That Should Exercise Caution

• Those with a prior history of persistent sexual dysfunction from oral finasteride. 
• People with underlying endocrine disorders or baseline sexual dysfunction. 
• Those sensitive to propylene glycol or alcohol-based carrier agents.

It should be mentioned that a history of side effects from oral finasteride does not mean that topical finasteride won’t work well for you; however, it does warrant a personalized, cautious approach. This approach might include starting with lower doses, extended monitoring, and communication with the prescribing physician about any potential symptoms.

Groups That Should Avoid Topical Finasteride

• Women who are pregnant or attempting to conceive. 
• People with severe scalp dermatitis or barrier dysfunction.
• Individuals with known allergy/hypersensitivity to finasteride or formulation components.

If I Can’t Tolerate Topical Finasteride, What Should I Do?

For users unable to tolerate topical finasteride due to side effects or scalp irritation, several evidence-based alternatives exist.

Pharmacological Alternatives

Low Dose Oral Minoxidil 

Oral minoxidil is a hair growth stimulant that bypasses the hormonal pathway entirely. Studies show high efficacy (e.g., 43% of men achieving excellent results with 5 mg), but it carries systemic risks such as hypertrichosis (excess body hair), fluid retention, and cardiovascular effects like tachycardia.^[24]Vano-Galvan, S., Pirmez, R., Hermosa-Gelbard, A., Moreno-Arrones, O.M., Saceda-Corralo, D., Rodrigues-Barata, R., Jiminez-Cauhe, J., Koh, W.L., Poa, J.E., Jerjen, R., de Carvalho, L.T., John, J.M., … Continue reading

Alternative Topical Anti-Androgens

Fluridil is a topical anti-androgen designed to degrade in water (i.e., blood), minimizing systemic exposure. Clinical data are limited but suggest efficacy without affecting serum testosterone or sexual function.^[25]Sovak, M., Seligson, A.L., Kucerova, R., Bienova, M., Hajduch, M., Bucek, M. (2002). Fluridil, a rationally designed topical agent for androgenetic alopecia: first clinical experience. Dermatologic … Continue reading

Clascoterone (17ɑ-proprionate) is an androgen receptor antagonist that competes with DHT at the follicle rather than reducing DHT production. It offers a different mechanism but is still under investigation for hair loss.^[26]Devjani, S., Ezemma, O., Kelley, K.J., Stratton, S., Senna, M. (2023). Androgenetic Alopecia: Therapy Update. Drugs. 83(8). 701-715. Available at: PMID: 37166619

Pyrilutamide is a non-steroidal anti-androgen that binds to the androgen receptor with high affinity. Like fluridil, it is designed to metabolize into an inactive form upon entering systemic circulation, theoretically offering a safety advantage over finasteride.^[27]Biospace. (2023). Kintor Pharma’s KX-826 and GT20029 for Treatment of Androgenetic Alopecia (AGA) and Acne Presented at AAD 2023. Biospace. Available at: … Continue reading

Non-Pharmaceutical Options

Microneedling creates micro-injuries in the scalp and stimulates growth factors (PDGF, VEGF) and activates Wnt/ꞵ-catening signaling, promoting hair regeneration even without concurrent drug use.^[28]Dhurat, R., Sukesh, M.S., Ayhad, G., Dandale, A., Pal, A., Pund, P. (2013). A Randomized Evaluator Blinded Study of Effect of Microneedling in Androgenetic Alopecia: A Pilot Study. International … Continue reading 

Low-level laser therapy (LLLT) devices use red light (650-655 nm) to stimulate mitochondrial activity in hair follicles, prolonging anagen and improving density with an excellent safety profile.^[29]Egger, A., Resnik, S.R., Aickara, D., Maranda, E., Kaiser, M., Wikramanayake, T.C. (2020).  Examining the Safety and Efficacy of Low-Level Laser Therapy for Male and Female Pattern Hair Loss: A … Continue reading 

Some botanical supplements have some 5ɑ-reductase inhibitory properties. Saw palmetto and pumpkin seed oil have been shown to have mild  5ɑ-reductase inhibition.^[30]Cho, Y.H., Lee, S.Y., Jeong, D.W., Choi, E.J., Kim, Y.J., Lee, J.G., Yi, H.Y., Cha, H.S. (2014). Effect of Pumpkin Seed Oil on Hair Growth in Men with Androgenetic Alopecia: A Randomized, … Continue reading,^[31]Pilar, P., 2010. Potency of a novel saw palmetto ethanol extract, SPET-085, for inhibition of 5alpha-reductase II. Advances in Therapy. 27(8). 555-563. Available at: … Continue reading  While less potent than finasteride (reducing DHT by ~30-40% vs. >60%), they may provide a viable “middle ground” for those seeking modest stabilization.

Final Thoughts

Topical finasteride offers a compelling middle path for those seeking the hair-growth benefits of 5-α-reductase inhibition with a lower likelihood of systemic side effects. But “lower” does not mean “none,” and responses vary widely depending on formulation, dose, skin permeability, and individual DHT sensitivity. The current research, while promising, remains short-term, and real-world patterns remind us that systemic exposure is still possible.

For many people, topical finasteride can be a safe, effective component of a broader hair-loss program. The key is approaching it strategically: start low, personalize dosing, choose the right vehicle, and monitor closely for changes. For others, especially those prone to hormonal side effects, alternatives ranging from anti-androgen topicals to non-pharmaceutical options may offer a better balance of efficacy and tolerability.

As with any AGA therapy, the best results come from matching the treatment to the individual, not the other way around.

After years of anticipation, we finally have the first-ever study testing topical dutasteride as a standalone treatment for androgenic alopecia (AGA). No microneedling, no formulations mixed with other ingredients, just topical dutasteride itself.

And the results?

Frankly, they are shocking.

According to the study, low-dose topical dutasteride outperformed oral finasteride for hair regrowth. 

On the face of it, this is so surprising that it borders on unbelievable, especially given the 5+ years of real-world data we’ve collected from our members. 

So, in this article, we’ll break down:

• What we previously knew about topical dutasteride.
• How real-world user experiences compare to clinical findings.
• What this new study claims.
• And why two major methodological problems force us to seriously question the results.

Interested in Topical Dutasteride?

Hair gains bigger than finasteride? Dutasteride makes this possible, if prescribed*

Take the next step in your hair regrowth journey. Get started today with a provider who can prescribe a topical solution tailored for you.

Click Here For 15% Off

*Only available in the U.S. Prescriptions not guaranteed. Restrictions apply. Off-label products are not endorsed by the FDA.

What We Knew About Low-Dose Topical Dutasteride Before This Study

Until now, only two small clinical studies have evaluated low-dose topical dutasteride. Both used it alongside microneedling and applied it just once every 1-4 weeks.

1. Nada et al. (2018): Microneedling + Topical Dutasteride vs. Microneedling Alone

Nada et al. reported that adding low-dose topical dutasteride to a structured microneedling regimen improved hair density and shaft thickness more than microneedling alone, while only slightly reducing serum DHT, likely without meaningful systemic hormonal impact.^[1]Nada, E.A., El-Dawla, R.E., El-Maged, W.M.A., Elmaged, M.A.A. (2018). Topical dutasteride with microneedling in treatment of male androgenetic alopecia. Sohag Medical Journal. 22(1). Available at: … Continue reading

30 men with AGA were randomized to either microneedling plus topical dutasteride 0.02% or microneedling alone for six months. Both groups received 13 microneedling sessions with a 1.5 mm Dermapen (12-needle cartridge) on a staggered schedule: weekly during the first 8 weeks, then gradually reduced to once every 2-4 weeks through month six. In the combination arm, up to 2 mL of 0.02% dutasteride 

1. Sanchez-Meza et al. (2022): Microneedling + Topical Dutasteride vs. Microneedling Alone

Sanchez-Meza et al. found that adding very low-dose topical dutasteride to microneedling produced greater clinical and trichoscopic improvement than microneedling with placebo, without reported sexual side effects and with much lower total dutasteride exposure than earlier work.^[2]Sanchez-Meza, E., Ocampo-Candiani, J., Gomez-Flores, M., Herz-Ruelas, M.E., Ocampo-Garza, J., Orizaga-Y-Quiroga, T.L., Martinez-Moreno, A., Ocampo-Garza, S.S. (2022). Microneedling plus topical … Continue reading

34 men with AGA were randomized to microneedling plus 1 mL of 0.01% topical dutasteride (~0.1 mg) or microneedling plus 1 mL of saline as a placebo. Both groups received three treatment sessions spaced 4 weeks apart using a Dr. Pen Ultima A6 device set to a 2.5 mm needle depth, and outcomes were assessed over a 16-20 week period.

While both these studies showed mild hair regrowth, the effect is not from topical dutasteride alone, nor from daily use. 

Furthermore, low-dose topical dutasteride showed almost no systemic dihydrotestosterone (DHT) suppression. 

Across these studies, bloodwork suggested:

• Little to no measurable DHT suppression
• Meaning minimal systemic absorption
• And therefore lower risk of systemic side effects

This makes sense. Dutasteride is a large, lipophilic molecule. At low concentrations, it tends to stay localized to the scalp unless dosing or penetration enhancers are significant.

What Did Real-World Users Experience?

Because early studies were promising, some of our members tried 0.01-0.02% topical dutasteride in the years that followed.

A dozen users also tracked blood DHT levels before and after treatment. 

The results? Strong localization with minimal regrowth.

• No meaningful changes in serum DHT (just normal daily variation of 10-15%). 
• Even among users applying up to 2 mL daily.
• Meaning: absorption remained low – as expected.
• But…users also reported very little growth.

Instead, most people saw hair maintenance, not cosmetic improvement. 

This aligns with the published studies: low-dose topical dutasteride appears to stabilize hair loss, with minimal systemic impact, but not drive substantial growth.

You can get more information about this and comparisons to topical finasteride here: 

• Topical Dutasteride Vs. Topical Dutasteride: The Dose Decides Everything (2025)
• Topical Finasteride: Where Do We Stand Today? (2025 Update)
• Topical Finasteride: Same Results, No Side Effects? (2022)

What Happened in the August 2025 Study?

This new randomized, double-blind, placebo-controlled study appeared to be the gold standard of topical dutasteride research.^[3]Panuganti, V.K., Mandala, P.K., Grandhi, V.R., Alluri, C.V., Mohammad, J., Rao, S., Dundigalla. (2025). A Randomized, Double-Blind, Placebo and Active Controlled Phase II Study to Evaluate the Safety … Continue reading  

It was the first study to test topical dutasteride:

• By itself (no microneedling).
• With daily use.
• Across multiple doses (0.01%, 0.02%, and 0.05%).
• Against both a placebo and oral finasteride.

On paper, this looked like the definitive study that we have long needed.

Study Design

135 men aged 20-60 with Norwood III vertex, IV, or V AGA were randomized across five treatment arms in a 2:2:2:2:1 ratio:

• 0.01% topical dutasteride (n=30)
• 0.02% topical dutasteride (n=30)
• 0.05% topical dutasteride (n=30)
• Oral finasteride 1 mg + placebo topical (n=30)
• Placebo topical + placebo oral (n=15).

All participants were Asian men, average age of ~38 years. Baseline hair loss severity was balanced across groups. 

Each 1 mL dose contained:

• 0.01% = 0.1 mg dutasteride
• 0.02% = 0.2 mg dutasteride
• 0.05% = 0.5 mg dutasteride 

Importantly, the solution was nearly 30% dehydrated alcohol, a known penetration enhancer. This choice may have implications for systemic absorption and hair-count interpretation, though the authors claim systemic exposure remained minimal. 

The researchers measured hair counts (total area hair counts) and hair widths (total area hair widths). Using a Dino-Lite microscope, researchers identified a 1.9 cm2 circular region at the vertex, clipped hairs to 0.5 – 1 mm, marked the center of the circle, and captured macrophotographs at baseline, week 12, and week 24.

The authors do not mention tattooing, ink permanence, or the use of a positioning device, which becomes critically important later.

The Study’s Reported Results

Here’s where the shock factor begins.

At 24 weeks, the study reported:

• 0.01% dutasteride: +32.32 hairs/cm2
• 0.02% dutasteride: +27.48 hairs/cm2
• 0.05% dutasteride: +75.52 hairs/cm2
• Oral finasteride: +41.21 hairs/cm2
• Placebo: 0.07 hairs/cm2

The headline claim: “0.05% topical dutasteride significantly outperformed oral finasteride (p=0.0083)”

This is a remarkable result, and one that contradicts every known real-world case we’ve observed at similar dosing. 

Hair-Width Improvements

All active groups increased hair thickness, with results very close to oral finasteride:

• 0.01% +6.68 μm.
• 0.02% +9.15 μm.
• 0.05% +11.59 μm.
• Finasteride: +10.68 μm.
• Placebo: +4.00 μm.

Only the 0.05% topical and finasteride groups significantly beat placebo. The 0.05% topical did not significantly outperform finasteride in hair-width metrics.

Global Photography Assessment (Investigator-Rated)

At 24 weeks, the percentage of participants rated as having “moderate improvement” or better (GPA ≥ +2) was:

• 0.05% topical: 68.97%.
• Finasteride: 21.43%.
• Placebo: 13.33%.

These numbers suggest a level of regrowth from 0.5 mg/week of topical dutasteride that we’ve simply never witnessed, not in our community, not in the medical literature, and not among clinicians who routinely prescribe topical dutasteride. 

Patient-Reported Outcomes (MHGQ)

By week 24, 96.55% of 0.05% topical users were satisfied with the hair on top of their heads. This is far above the finasteride group (71.43%) and far above the placebo (33.33%).

Again, the magnitude of the difference warrants scrutiny.

Serum Hormone Changes

This is where things do align with real-world experiences of low-dose topical users.

DHT Reductions

• Finasteride: 11% to -27%.
• 0.05% topical dutasteride: around -9% to -11%.

Testosterone Increases

• Finasteride: +20%.
• Topical dutasteride: modest, non-significant changes.

The authors emphasize that topical dutasteride caused minimal systemic effects.

This is consistent with our members’ lab data – but inconsistent with the hair-growth magnitude reported.

Pharmacokinetics (How Much Enters the Bloodstream)

According to the PK data: 

• Plasma dutasteride levels were near or below quantification limits.
• A few values spiked as high as 2555 pg/mL, suggesting occasional high absorption events.
• Dutasteride remained detectable at day 168, implying accumulation over time.

The authors interpret this as “low systemic exposure”. But variability this large raises questions.

Safety Findings

Across the entire study, no serious adverse events were reported, no withdrawals due to safety, minimal skin irritation, and all groups showed mild effects like “glazing” at similar rates.

This matches expectations for low-dose topicals.

So, Why Don’t the Results Match Real-World Experience?

For more than five years, we’ve tracked user outcomes from low-dose topical dutasteride at comparable or even higher weekly doses than used in this study.

Not once have we seen:

• Regrowth exceeding oral finasteride.
• Cosmetic transformation from 0.05% topical alone.
• Hair-count improvements anywhere near +75 hairs/cm2.

Even in dermatology clinics across the world, this simply isn’t observed. So, why would this study find such dramatically different results?

It comes down to two major methodological problems – both related to hair counts.

Problem #1: Baseline Hair Counts That Defy Biology

The average baseline hair density reported in the study was 305-330 hairs/cm2. 

For context: 

• A healthy adult without hair loss typically has 100-250 hairs/cm2. 
• Men with Norwood III-V AGA typically have 25-100 hairs/cm2 in the vertex.
• Yet this study reports 300+ hairs/cm2 in balding men.

This would mean that severely balding scalps had triple the hair density of a normal, non-balding scalp, and that hair counts exceeded what is physiologically plausible.

Why might this happen?

Possible Explanations

Vellus hairs were counted.

• The study never defines a diameter cutoff.
• Best practice is to exclude hairs ≤40 µm.
• Counting vellus hairs inflates numbers dramatically. 

The measurement area was bigger than stated.

• The paper claims 1 cm2.
• Even a small mismeasurement could triple hair counts.

Manual counting errors.

• The study doesn’t specify software use. 
• Manual hair counting is outdated and error-prone.

None of these possibilities inspires confidence in the baseline data.

Problem #2: The Measurement Circle Moves Between Photos

This is the more serious problem, and the one most likely to invalidate the findings entirely.

When examining the study’s published before-and-after images, the measurement circles:

• Change location.
• Change size.
• Change shape.
• Appear hand-drawn.
• Clearly do not track the same exact scalp area over time.

Take a close look at these images; the center point marks do not appear to be consistent (at least from these photos). This means that you really can’t compare the improvements over time, as the follow-up hair counts would have been conducted in slightly different areas of the scalp!

This is an enormous methodological flaw.

A shift of just 1-2 millimetres in circle placement can change hair counts by 50% or more, something we demonstrated in our 2021 publication.^[5]Jnr, R.E., Ruiz, S. (2021). Conflicting Reports Regarding the Histopathological Features of Androgenic Alopecia: Are Biopsy Location, Hair Diameter Diversity, and Relative Hair Follicle … Continue reading

Yet the improvements reported in this study were around 10-30%.

Meaning: These “improvements” could be fully explained by inconsistent circle placement, not actual regrowth. 

This alone is enough to call the validity of the hair-count data into question. 

Final Thoughts

This is one situation where we at PHH trust the real-world experiences of our members over a randomized, controlled clinical trial, because while the study appears rigorous on the surface, its hair-counting methods reveal inconsistencies significant enough to undermine its conclusions. 

All available evidence still supports the following: low-dose topical dutasteride (0.01-0.05%) localizes well to the scalp, minimally suppresses serum DHT, effectively slows or stops hair loss, and rarely produces meaningful regrowth, whereas high-strength topical dutasteride (≥0.1%) is more likely to leak systemically, carry a greater risk of side effects, and generate visible regrowth approaching the results of oral finasteride.

Finasteride is among the most effective drugs for androgenic alopecia. And while side effects are often overstated, it can lead to reduced libido or lowered sperm counts in some men. For this reason, many choose topical versus oral finasteride, hoping to limit the drug’s DHT-reducing effects to the scalp. But at certain doses, even topical finasteride can become systemic. So, to minimize side effects, which finasteride dosage, formula and application is best? 

In this article, we’ll review 

• About oral versus topical finasteride
• Why topical finasteride can still go systemic
• Why choosing the lowest percentage solution isn’t the only answer
• How to maximize finasteride gains, while minimizing side effects

Interested in Topical Finasteride?

Low-dose & full-strength finasteride available, if prescribed*

Take the next step in your hair regrowth journey. Get started today with a provider who can prescribe a topical solution tailored for you.

Click Here For 15% Off

*Only available in the U.S. Prescriptions not guaranteed. Restrictions apply. Off-label products are not endorsed by the FDA.

About Finasteride 

Finasteride, also known under the brand name Propecia or Proscar, is a prescription medication approved by the FDA for the treatment of androgenic alopecia (AGA). The anti-androgen works by reducing the production of Dihydrotestosterone (DHT), a hormone linked to pattern hair loss. In use since 1992, Finasteride is among the most powerful and well-studied drugs for hair loss.

Oral Finasteride

Oral finasteride stops AGA progression in 80-90% of men and, on average, leads to a 10% increase in hair count over two years.^[1]https://www.sciencedirect.com/science/article/pii/S0022202X15529357 For men wanting a “hands-off” approach to hair maintenance, oral finasteride can be an excellent option. With a once-daily pill, it’s expected that hair loss will stop at approximately 6 months, and thereafter, improve.

However, oral finasteride isn’t for everyone. While the risk of side effects are often overstated online, the drug appears to reduce libido in a certain percentage of men. Oral finasteride can also temporarily lower sperm counts, which might make conception more difficult during its first six months of use. In some men, the use of finasteride appears to increase anxiety and/or depression. While the true incidence and magnitude of these reports are hard to discern, it’s understandable that many are weary of taking this once daily pill.

Fortunately, recent improvements in finasteride’s delivery may mean we no longer need to throw the proverbial baby out with the bathwater.

Topical Finasteride

The biggest reason people seek out topical finasteride (instead of oral finasteride) is because they want to minimize systemic exposure to the drug, and in doing so, localize finasteride’s effects to the scalp.

While research is still in the early stages, evidence suggests that topical finasteride can produce similar levels of hair regrowth compared to oral finasteride, with a significantly reduced incidence of side effects.

Topical finasteride works identically to its oral counterpart: by inhibiting the type II 5-alpha reductase enzyme to reduce DHT. It is designed to target scalp DHT instead of systemic DHT levels.

However, limiting finasteride’s reach to scalp, not serum, DHT is harder than perhaps anticipated. To understand why, let’s take a closer look at scalp versus serum DHT.

Serum vs Scalp DHT 

There’s a lot of evidence that the hormone DHT is directly implicated in androgenic alopecia. In fact, research directly links DHT to all three of AGA’s defining characteristics:

1. Increased telogen:anagen ratio. DHT’s influence on DKK-1 expression increases hair shedding
2. Increased anagen cycling. DHT’s effects on signaling pathways limit the growth phase of hairs 
3. Hair follicle miniaturization. DHT’s effects on dermal papilla sizing thins hair with each cycle 

There are a wide variety of DHT reducers available, including prescription drugs, over-the-counter products, intradermal injections, and even herbal supplements. Finasteride reduces DHT in two ways. 

1. Oral finasteride reduces DHT everywhere in the body. Beyond just the scalp, it reduces DHT in the blood, brain, and prostate. 
2. Topical finasteride attempts to reduce DHT only where it is applied – in the scalp – with minimal effects on DHT levels elsewhere.

However, it’s far easier than most realize for topical finasteride to go systemic. And when it does, it potentially reduces DHT everywhere – leading to the very side effects it’s meant to prevent.

Topical Finasteride Can Still Go Systemic

Why? When it comes to lowering DHT (the goal of the drug), finasteride has a highly-sensitive, dose-dependent response curve. This means that while 0.01 mg of finasteride barely reduces any DHT at all, 0.1 mg reduces almost as much DHT as 5 mg, a much larger dose.

This implies that when applying topical finasteride, only a tiny fraction of it needs to go systemic in order to produce the same DHT-lowering effects as oral finasteride. If this happens, the purpose of using the topical formulation is completely defeated. 

Research suggests a 1% topical finasteride formulation, applied twice daily, is ‘non-inferior,’ meaning equivalent, to 1 mg oral finasteride tablets.^[2]https://www.ncbi.nlm.nih.gov/pubmed/19172031 And while that’s a positive in terms of hair growth, using this amount topically twice daily pretty much guarantees systemic absorption. In other words, if 1% topical is the equivalent of 1 mg oral, we can expect it to reduce serum DHT levels by 71%.

So what if we choose a formula with even lower percentages of the active drug? A study on 0.25% topical finasteride showed just a 35% reduction in serum DHT levels versus 55% for the oral medication, and yet similar outcomes for hair regrowth in both oral and topical groups.^[3]https://onlinelibrary.wiley.com/doi/10.1111/jdv.17738

So what if we go even lower? A study on 0.005% alcohol-based topical finasteride instructed participants to use the formulation twice daily, with 1 mL applied per session.^[4]https://dx.doi.org/10.3109%2F09546639709160517 This led to no appreciable changes in serum DHT levels… meaning that for this ultra-low topical formulation, there was little-to-no systemic absorption (and presumably, few-to-no side effects). The good news? This group still experienced great hair growth outcomes.

So Just Reach for the Lowest Percentage, Yes?

It’s tempting from the above to infer we’ve reached the end of our story. As long as we reach for the lowest percentage of topical finasteride, we can be free from worries about the drug’s systemic effects. But, reality is a bit more complicated than that.

Systemic absorption isn’t just about dilution percentages. Topical finasteride’s systemic absorption actually depends on (at least) for variables:

1. The drug’s formulation. Common carrier agents include alcohol and propylene glycol.
2. The amount applied per use. The amount of topical finasteride applied to the scalp greatly varies.
3. The application frequency. Applying the drug twice per day can more than double its effects on serum DHT. 
4. The days of application. Topical finasteride can take many days to “leak” into the blood before its final effects on serum DHT are realized.

For an example, see this figure from a 2014 study measuring how one versus two applications of 1 mL of 0.25% topical finasteride affected serum DHT levels.^[5]https://www.ncbi.nlm.nih.gov/pubmed/25074865 

Over a 24-hour period, what were the findings?

• One application (i.e., 1 mL of 0.25% topical finasteride) lowered blood DHT levels by ~20%
• Two applications (i.e., 2 mL total) lowered blood DHT levels by ~70%

As such, we need to factor in these variables if we plan on sticking with topical finasteride for the long-term. Otherwise, we risk lowering our DHT levels to the same degree as 1 mg of oral finasteride, which would defeat the purpose of using the topical in the first place.

Topical Finasteride and Serum DHT: What Do The Clinical Studies Say?

Let’s take a closer look at some of the studies mentioned above. In addition to the percentage of active drug in the formula, there are a few more variables to understand. How much of the topical was applied, and which carrier agents were used?

The table below shows how even a .25% formula, for example, can reduce DHT in the serum by 24-70% 

Based on this table, our total mg of daily finasteride exposure is probably the biggest factor in determining systemic leakage. And our total daily exposure (in mg) is a function of topical finasteride dilution (%) and the amount (mL) applied daily.

Knowing this, we can turn this table into a chart and sort it by mg of daily exposure. In doing so, we see a clear trend:

The good news? At both extremes of this chart – 0.091 mg and 2.275 mg daily – topical finasteride was shown to produce clinical results in improving hair parameters. Based on this, if we’re going for topical finasteride, we probably want to be prescribed topical finasteride solutions that net us daily exposure volumes of 0.228 mg and lower. After all, at 0.091 mg of topical finasteride daily, no systemic effects on DHT were observed.^[6]https://www.tandfonline.com/doi/abs/10.3109/09546639709160517

In other words, low dilutions (i.e., 1-2 mL of 0.005% to 0.02% of topical finasteride) confer significant benefits but at reduced risks of side effects due to lower systemic absorption – provided that guidelines for daily amounts (in mL) are also followed.

So What’s the Perfect Amount and Formula?

Our analyses from member-submitted lab tests and the clinical data suggest that 10-15% of topical finasteride will enter the bloodstream, at least when it’s formulated with alcohol and/or propylene glycol as carrier ingredients (as most compounding pharmacies do). So, if we apply 1-2 mL of 0.005% to 0.02% topical finasteride, this might equate to just 0.01-0.03 mg of systemic drug exposure.

For the overwhelming majority of people, that’s not enough systemic leakage to significantly lower DHT levels in the body. But it is enough to produce great hair loss outcomes. 

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Long-story short: stick to 1-2 mL of 0.005% to 0.02% topical finasteride solutions. This equates to roughly 0.1-0.2mg of daily finasteride exposure to the scalp. Any more than that, and there’s risk of significant systemic leakage, which defeats the purpose of using topical finasteride altogether.

How to Maximize Gains and Minimize Side Effects

Maximizing gains while minimizing the side effects of finasteride can be done, but it’s not a perfect science. We’ve outlined several tips below that we think might help. Due to individual variance, the most important step is to always start with testing.

1. Get Lab Tests for DHT

The goal with topical finasteride is to reduce the risk of side effects. To do this, we must minimize the amount of finasteride that leaks into the bloodstream. The best way to do this isn’t to rely on estimated metrics from clinical studies, but to collect personal data.

Get a serum DHT test before using the topical to establish a baseline. Then, DHT levels should be retested at one month to gauge just how much is going systemic. Testing is easier than most expect, and in our experience, the expenses are worth the peace of mind.

If future lab tests deviate from baseline, it’s an indication of just how much topical finasteride is going systemic. According to the clinical data, 30 days of application is more than enough time for finasteride to saturate at its maximum levels in the scalp and serum. 

As such, measuring DHT levels after one month of finasteride use offers a great reference point to see if topical finasteride is impacting serum DHT levels. If needed, changes can be made to the application or use frequency depending on any changes to your blood levels of DHT.

2. Understand That DHT Levels Fluctuate Diurnally

Keep in mind, some fluctuation in DHT levels is normal. DHT levels fluctuate throughout the day and across seasons. As such, 15-20% differences across tests are normal and expected. Anything beyond 20% suggests that topical finasteride might be having slight systemic effects.

Because of this fluctuation, however, it’s important to get blood draws done at the same time of day – preferably in the morning and while in a fasted state. Also, try not to make drastic changes to diet, lifestyle, or environment prior to testing. Heavy drinking, deviations from a typical daily diet, the introduction of creatine powders, and/or sleep deprivation can all influence DHT levels and muddy test results. In the 3-5 days prior to the second test, try to keep things as they were when you first went in for testing.

3. Avoid supplementing with Quercetin and/or Creatine

Maintaining systemic DHT levels, while maximizing the effects of finasteride, isn’t just about the drug. There are other activities that could potentially affect DHT levels. Supplementing with quercetin and/or creatine is one common mistake that could impact results.

Studies on mice suggest that quercetin can inhibit the DHT-reducing effects of finasteride.^[7]https://joe.bioscientifica.com/view/journals/joe/181/3/493.xmlWhile the translatability to humans has not yet been studied, the dosages used in these mouse models were comparable to what humans typically consume from quercetin supplements. As such, it may be best for those using finasteride to avoid this supplement.

When it comes to creatine, one study found that in training athletes, creatine supplementation increased serum DHT levels by over 70%.^[8]https://pubmed.ncbi.nlm.nih.gov/19741313/ While the study was small, we have to reconcile these findings with the reality that for the overwhelming majority of training athletes, creatine is unnecessary. Bodybuilders can still look great without using it, and so can the every-day gym goer. Competitive bodybuilders are, however, a different story.

4. Set Realistic Expectations and Track Progress

Finasteride is the best-studied intervention for androgenic alopecia. In order to appreciate its full effects, consider the following:

1. Know the timeline for results. Clinical studies show that finasteride improves pattern hair loss outcomes in 80-90% of men. Having said that, cosmetic degrees of hair regrowth don’t often occur until after 10-12 months of treatment. Moreover, the drug’s full effects typically take two years to manifest, with the biggest degrees of cosmetic regrowth occurring between year one and year two. As such, don’t expect any miracles in the first six months, it may take the full two years to see an effect. 
2. Track progress. It’s hard to know if something is improving without objective measurements. While not all of us have access to trichoscopic hair-counting equipment, most of us do have a smartphone, which can easily be used to take photos to track progress (particularly when the photosets are standardized). This can be done relatively effortlessly. 

Following the tips above allows for the best possible shot at measurable hair growth results, while minimizing the potential effects of systemic DHT reduction.

Summary

Oral finasteride works great for male pattern hair loss, but by significantly reducing serum DHT, it can cause unwanted side effects. 

Topical finasteride was developed as a solution, with a goal to reduce DHT in the scalp only. But when applied in high percentages or large amounts, it too, can go systemic and reduce serum DHT levels. 

To minimize the side effects of finasteride without missing out on the benefits, stick to 1-2 mL of 0.005% to 0.02% topical finasteride solutions. This equates to roughly 0.1-0.2mg of daily finasteride exposure to the scalp. 

The best way to ensure a reduced risk for side effects is to track serum DHT levels. Establish a baseline by taking one test before using finasteride, then test again one month later. 

Dihydrotestosterone (DHT) is a potent androgen hormone that can significantly impact hair loss. Its activity, however, isn’t just restricted to the scalp. What’s more, hair loss is a multifactorial condition, with a wide range of causes. As such, the solution to hair loss is much more complicated than simply eliminating DHT.

Many natural or pharmaceutical therapies seek to reduce, or rather, rebalance DHT levels. While lowering DHT can slow or even reverse hair loss, the hormone itself plays vital roles in sexual function, mood regulation, and overall well-being. Therefore, the goal should not be total suppression, but rather modulation that considers the balance between hair health and systemic androgen levels.

In this article, we will rank both natural and pharmaceutical DHT blockers from weakest to strongest, based on research, effectiveness, and risk of side effects.

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Understanding DHT: Why Blocking It Helps (and Hurts)

DHT is derived from testosterone through the enzyme 5-alpha-reductase. Once formed, DHT binds to androgen receptors and plays a major role in androgenic alopecia (AGA). In hair follicles genetically sensitive to DHT, such as those on the crown and frontal scalp, the hormone acts as a signal for miniaturization. Over time, the follicle shrinks, producing thinner, shorter hairs until it eventually becomes dormant.^[1]York, K., Meah, N., Bhoyrul, B., & Sinclair, R. (2020). A review of the treatment of male pattern hair loss. Expert Opinion on Pharmacotherapy. 21(5). 603-612. Available at: … Continue reading

By reducing DHT levels or blocking its receptor binding, therapies can interrupt this miniaturization cascade. The goal is to prevent DHT from triggering the cellular changes that cause follicles to shrink and enter a premature resting (telogen) phase. AGA is influenced not just by DHT levels but also by individual receptor sensitivity, local inflammation, and oxidative stress.

However, because of DHT’s wide-reaching activity, side effects of its reduction can include sexual dysfunction, decreased motivation, and mood changes, especially in individuals who are more hormonally sensitive. As such, careful consideration of different therapies and their potential impacts is essential if you choose to use a DHT-blocking treatment.^[3]Traish, A. M., Melcangi, R. C., Bortolato, M., Garcia-Segura, L. M., & Zitzmann, M. (2015). Adverse effects of 5α-reductase inhibitors: what do we know, don’t know, and need to know?. Reviews … Continue reading

Ranking the DHT Blockers: From Mild to Potent

We’ll rank DHT blockers based on their potency, as well as on the quality of evidence supporting their use for hair loss. You can learn more about our treatment metrics, including evidence quality, in our article.

Tier 1 – Mild / Natural DHT Blockers

Natural treatments, typically based on oils and herbs, are generally more gentle than pharmaceutical options. They tend to be less potent, but have far fewer side effects and are not typically subject to the same stringent regulation as pharmaceuticals.

EGCG (Evidence Quality – 6%)

Epigallocatechin gallate (EGCG), a catechin compound found in green tea, is another naturally derived compound that has attracted interest for its potential to influence hair follicle biology. As a potent antioxidant and anti-inflammatory molecule, EGCG helps protect follicular cells from oxidative stress and inflammation, both of which are exacerbated by androgen activity. 

 

EGCG appears to enhance cell-survival pathways such as Akt and Erk, supporting follicular cell proliferation while suppressing apoptotic signals that can trigger hair follicle regression.^[5]Kwon, O. S., Han, J. H., Yoo, H. G., Chung, J. H., Cho, K. H., Eun, H. C., & Kim, K. H. (2007). Human hair growth enhancement in vitro by green tea epigallocatechin-3-gallate (EGCG). … Continue reading

Laboratory studies also indicate that EGCG can partially inhibit 5AR, reducing the local generation of DHT.^[6]Hiipakka, R. A., Zhang, H. Z., Dai, W., Dai, Q., & Liao, S. (2002). Structure–activity relationships for inhibition of human 5α-reductases by polyphenols. Biochemical Pharmacology. 63(6). … Continue reading However, while this study showed that EGCG can inhibit 5AR in cell-free experiments, it did not have the same impact in cells. This suggests that it may not be able to enter cells and would have reduced impacts in humans.

This seems to be the case, and clinical evidence for EGCG in the treatment of hair loss remains limited. A small pilot study of topical EGCG found no visible changes in hair, although this research was conducted in people with no hair loss disorders.^[7]Kwon, O. S., Han, J. H., Yoo, H. G., Chung, J. H., Cho, K. H., Eun, H. C., & Kim, K. H. (2007). Human hair growth enhancement in vitro by green tea epigallocatechin-3-gallate (EGCG). … Continue reading Despite the lack of large-scale human trials, molecular findings do suggest EGCG contributes meaningfully to the cellular environment that supports hair growth and protection.

Catechins from green tea infusions are generally well tolerated. However, supplements should be used cautiously at high doses, particularly above 800 mg per day, as they have been linked to liver enzyme elevations in sensitive individuals.^[8]EFSA Panel on Food Additives and Nutrient Sources added to Food (ANS), Younes, M., Aggett, P., Aguilar, F., Crebelli, R., Dusemund, B., Filipič, M., Frutos, M. J., Galtier, P., Gott, D., … Continue reading

You can read more about the evidence for using EGCG for hair loss in our article here.

Pumpkin Seed Oil (Evidence Quality – 49%)

Pumpkin seed oil (PSO) is one of the most extensively studied non-pharmaceutical treatments for hair loss. In general, it is mild and well-tolerated. Its effects appear to arise from its profile of phytosterols and essential fatty acids, such as linoleic and oleic acid. These compounds have been shown to exhibit mild 5AR inhibitory activity in laboratory studies, potentially reducing local DHT formation in scalp tissues.^[9]Azizi, A., Mumin, N. H., & Shafqat, N. (2021). Phytochemicals with anti 5-alpha-reductase activity: a prospective for prostate cancer treatment. F1000Research. 10. 221. Available at: … Continue reading,^[10]Liang, T., & Liao, S. (1992). Inhibition of steroid 5α-reductase by specific aliphatic unsaturated fatty acids. Biochemical Journal. 285(2). 557-562. Available at: … Continue reading

Beyond hormonal modulation, pumpkin seed oil provides antioxidant and anti-inflammatory support, which can help protect hair follicles from oxidative damage and microinflammation – two key contributors to progressive miniaturization.^[11]Fahim, A. T., Abd-El Fattah, A. A., Agha, A. M., & Gad, M. Z. (1995). Effect of pumpkin-seed oil on the level of free radical scavengers induced during adjuvant-arthritis in rats. Pharmacological … Continue reading

A clinical trial carried out in Korea made waves in 2014 when it reported a 40% increase in hair count after 24 weeks. However, the formulation, Octa-Sabal Plus, included multiple additional herbal compounds, alongside pumpkin seed powder, not oil. This means we can’t attribute the growth reported to pumpkin seed oil.^[12]Cho, Y. H., Lee, S. Y., Jeong, D. W., Choi, E. J., Kim, Y. J., Lee, J. G., & Cha, H. S. (2014). Effect of pumpkin seed oil on hair growth in men with androgenetic alopecia: a randomized, … Continue reading 

You can read more about the controversial PSO study here.

Cold-pressed pumpkin seed oil is typically taken orally at doses ranging from 400 to 1000 mg daily, with results accumulating gradually over several months. The compound is generally well tolerated, with gastrointestinal discomfort being rare and mild.^[13]Hong, H., Kim, C. S., & Maeng, S. (2009). Effects of pumpkin seed oil and saw palmetto oil in Korean men with symptomatic benign prostatic hyperplasia. Nutrition Research and Practice. 3(4). … Continue reading Although PSO alone is unlikely to reverse established AGA, it may serve as a gentle adjunct for individuals seeking natural or preventive strategies to support long-term scalp and hair health.

Saw Palmetto (Evidence Quality – 54%)

Saw palmetto (Serenoa repens) is one of the most widely studied natural 5AR inhibitors and is sometimes called “nature’s finasteride.” It appears to reduce DHT by inhibiting Type II 5AR, reducing the binding of DHT to androgen receptor sites and increasing the conversion of DHT to a weaker metabolite called androstanediol.^[14]Suzuki, M., Ito, Y., Fujino, T., Abe, M., Umegaki, K., Onoue, S., Noguchi, H., & Yamada, S. (2009). Pharmacological effects of saw palmetto extract in the lower urinary tract. *Acta … Continue reading

Importantly, saw palmetto appears to reduce DHT selectively, with research showing decreases in DHT in the prostate but not in the blood. As such, it may cause fewer side effects than systemic DHT reducers.^[15]Fagelman, E., & Lowe, F. C. (2001). Saw palmetto berry as a treatment for BPH. Reviews in Urology. 3(3). 134-138. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1476047/

Clinical studies have shown modest impacts of saw palmetto on hair loss. In one study, participants using oral extracts over several months showed reductions in hair shedding, increases in hair density, and subjective improvements in scalp coverage and hair quality.{ Importantly, however, this was an open-label study, where participants and researchers both knew what product they were receiving, so is not as strong a form of evidence as a randomzied controlled trial (RCT).^[16]Rossi, A., Mari, E., Scarno, M., Garelli, V., Maxia, C., Scali, E., Iorio, A., & Carlesimo, M. (2012). Comparative effectiveness of finasteride vs Serenoa repens in male androgenetic alopecia: a … Continue reading 

In a recent RCT, a standardized, proprietary saw palmetto extract was given as either a 400mg oral capsule or 5 ml of topical formulation and compared to relevant controls. The study found a significant reduction in hair shedding in both oral and topical groups compared to their controls, alongside an increase in hair density of 5% and 7.5% respectively. However, this study also had significant drawbacks. For example, measurements of hair density were not well defined and may therefore include vellus hairs, which do not contribute to visible hair. Despite this, the study does provide some support for the use of saw palmetto in decreasing hair shedding and increasing hair thickness.^[17]Sudeep, H. V., Rashmi, S., Jestin, T. V., Richards, A., Gouthamchandra, K., & Shyamprasad, K. (2023). Oral and topical administration of a standardized saw palmetto oil reduces hair fall and … Continue reading

Evidence from benign prostatic hyperplasia suggests that an oral dose of 320 mg per day is optimal, with increases in dose above that resulting in no further improvements. For topical use, concentrations around 0.5 – 1% applied once or twice daily are common. Both routes are well tolerated, with infrequent reports of mild gastrointestinal discomfort or skin irritation. 

You can read about the differences between saw palmetto and finasteride in our article here.

Tier 2 – Over-the-Counter Pharmaceutical Options

Over-the-Counter Pharmaceutical Options bridge the gap between gentle natural therapies and prescription-strength DHT blockers, potentially offering clinically supported benefits with relatively low systemic risk.

Ketoconazole Shampoo (Evidence Quality – 54%)

Originally developed as an antifungal agent, ketoconazole helps normalize the scalp environment by reducing inflammation, fungal overgrowth, and excess sebum, all of which can worsen AGA. Beyond its antifungal activity, laboratory and clinical research suggest that ketoconazole exerts mild local antiandrogenic effects, likely through partial inhibition of 5AR and modulation of DHT activity within the scalp. 

Clinical evidence for men is stronger than for women. One 21-month study using 2% ketoconazole shampoo showed progressive improvement in hair shaft diameter and percentage of hairs in the growth (anagen) phase, reversing the slow decline seen in untreated AGA.^[18]Piérard-Franchimont, C., De Doncker, P., Cauwenbergh, G., & Piérard, G. E. (1998). Ketoconazole shampoo: effect of long-term use in androgenic alopecia. Dermatology. 196(4). 474-477. Available … Continue reading

Another study, which compared Ketoconazole with other shampoos, found that 1% ketoconazole reduced hair shedding by 17%, improved anagen hair by 4.9%, and lowered scalp sebum levels.^[19]Piérard-Franchimont, C., Goffin, V., Henry, F., Uhoda, I., Braham, C., & Piérard, G. E. (2002). Nudging hair shedding by antidandruff shampoos: A comparison of 1% ketoconazole, 1% piroctone … Continue reading Studies also show that ketoconazole performs well as an adjunct therapy, with synergistic effects when combined with finasteride.^[20]Perez, B. S. H. (2004). Ketoconazole as an adjunct to finasteride in the treatment of androgenetic alopecia in men. Medical Hypotheses. 62(1). 112-115. Available at: … Continue reading 

Evidence in women is limited, with only one published study investigating ketoconazole solution, rather than shampoo. They compared 2% ketoconazole to 2% minoxidil and reported meaningful regrowth in both groups, with ketoconazole producing improvements by the six-month mark and causing far fewer side effects.^[21]El-Garf, A., Mohie, M., & Salah, E. (2019). Trichogenic effect of topical ketoconazole versus minoxidil 2% in female pattern hair loss: a clinical and trichoscopic evaluation. Biomedical … Continue reading

Ketoconazole is generally well tolerated. Mild irritation, dryness, or temporary scalp tightness may occur, especially with 2% formulations or frequent use. Most regimens recommend applying it 2–3 times per week, leaving the shampoo on the scalp for 3–5 minutes before rinsing.

You can read our breakdown of the research into ketoconazole shampoos here.

You can also read about why 2% ketoconazole might be a better choice than 1% here.

Tier 3 – Prescription Pharmaceutical DHT Blockers

Prescription Pharmaceutical DHT Blockers represent the most potent and clinically validated options, offering stronger and more predictable suppression of DHT than natural therapies but with a greater need for careful monitoring of side effects.

Topical Finasteride (Evidence Quality – 69%)

Topical finasteride represents a new, more targeted approach to DHT inhibition, delivering the drug directly to the scalp while aiming to minimize systemic exposure. Like its oral counterpart, it blocks the Type II 5-alpha reductase enzyme. However, by focusing this activity locally within the hair follicle, topical formulations can achieve substantial reductions in scalp DHT while maintaining serum levels that are a fraction of those seen with oral dosing. This distinction is clinically important for individuals concerned about systemic side effects such as decreased libido or hormonal shifts.

Clinical research has consistently shown that topical finasteride can achieve similar improvements in hair density and regrowth as oral therapy. One 24-week study showed a 34.5% decrease in DHT, compared to 55.6% for oral finasteride. However, plasma concentrations were 100 times lower, indicating that systemic exposure is greatly reduced.^[22]Piraccini, B. M., Blume-Peytavi, U., Scarci, F., Jansat, J. M., Falqués, M., Otero, R., Tamarit, M. L., Galván, J., Tebbs, V., Massana, È., on behalf of the Topical Finasteride Study Group. … Continue reading

Topical finasteride is particularly appealing to men who respond well to oral therapy but wish to lower the risk of systemic adverse effects. When applied once daily at concentrations between 0.1% and 0.25%, it can stabilize shedding within four to six months, with visible improvements generally continuing over the course of a year.^[23]Mazzarella, G. F., Loconsole, G. F., Cammisa, G. A., Mastrolonardo, G. M., & Vena, G. A. (1997). Topical finasteride in the treatment of androgenic alopecia. Preliminary evaluations after a … Continue reading For optimal results, it can be combined with topical minoxidil to stimulate regrowth through complementary pathways.^[24]Wang, H., Chen, B., & Hong, X. (2020). The efficacy and safety of finasteride combined with topical minoxidil for androgenetic alopecia: A systematic review and meta-analysis. *Journal of … Continue reading  

Our members can find the ultimate guide to finasteride here.

Dutasteride (Evidence Quality – 77%)

Dutasteride is the most potent 5AR inhibitor currently available, targeting both Type I and Type II isoenzymes. This dual inhibition results in serum DHT reductions of up to 90 – 95%, creating a profoundly anti-androgenic environment within scalp follicles.^[25]Roehrborn, C. G., Marks, L. S., Fenter, T., Freedman, S., Tuttle, J., Gittleman, M., Morrill, B., & Wolford, E. T. (2004). Efficacy and safety of dutasteride in the four-year treatment of men … Continue reading Clinically, this translates into faster and often more pronounced regrowth compared to finasteride, particularly in individuals with advanced hair thinning.

Because dutasteride suppresses DHT more comprehensively, it may pose a slightly higher risk of hormonal side effects such as gynecomastia or reduced libido. However, head-to-head studies have suggested superior efficacy for dutasteride in both short-term and long-term endpoints. 

A meta-analysis, which combines results from multiple studies, indicated that dutasteride showed better efficacy in treating AGA.^[26]Zhou, Z., Song, S., Gao, Z., Wu, J., Ma, J., & Cui, Y. (2019). The efficacy and safety of dutasteride compared with finasteride in treating men with androgenetic alopecia: a systematic review and … Continue reading These results suggest that dutasteride is ~3 times more potent than finasteride in blocking Type II 5α-reductase and up to 100 times more potent against Type I. This dual inhibition reduces scalp DHT levels by over 50%, compared to approximately 41% with finasteride, leading to greater prevention of follicular miniaturization and enhanced regrowth response with similar levels of adverse effects.

Dutasteride has a relatively low evidence quality score compared to finasteride, though this is largely due to there being fewer studies. The studies that do investigate dutasteride have shown higher potency and effectiveness.

For detailed information on clinical trials, including dutasteride, check out our comprehensive summary.

Topical dutasteride formulations are now under active investigation. Concentrations ranging from 0.01% to 0.05% have produced significant gains in target-area hair counts, with studies suggesting that improvements associated with oral formulations can be achieved without drops in serum DHT.^[27]Panuganti, V. K., Madala, P. K., Grandhi, V. R., Alluri, C. V., Mohammad, J., KSSVV, S. R., & Dundigalla, M. R. (2025). A randomized, double-blind, placebo and active controlled Phase II study to … Continue reading

 

A 2018 randomized clinical study further demonstrated that topical dutasteride (0.02%) combined with microneedling significantly improved hair shaft thickness and patient satisfaction compared with microneedling alone, without notable systemic absorption or hormonal side effects. These findings suggest that localized delivery of dutasteride may enhance follicular response while minimizing systemic exposure and related adverse effects.^[29]Nada, E.A., El Sharkawy, R.E.E.D., Abd El-Maged, W. M., & Abo Elmagd, M. A. (2018). Topical dutasteride with microneedling in treatment of male androgenetic alopecia. Sohag Medical Journal. … Continue reading

Similarly, research published in 2024 looked into the impact of microneedling. However, in this study, topical dutasteride was combined with minoxidil. They found similar improvements in hair density and hair width in participants who had topical dutasteride and minoxidil treatment to those in patients who had oral dutasteride and topical minoxidil.^[30]Abu Obeid, M. N., Abdel Fattah, N. S., Elfangary, M. M., & Al Husseni, R. M. (2024). Comparison between Topical Minoxidil 5% Alone versus Combined with Dutasteride (Topical 0.02% through … Continue reading These results suggest that, in combination with other therapies (minoxidil or microneedling), topical dutasteride may be able to produce similar results to oral formulations but with a significantly lower chance of side effects.

A newly published Phase II trial has also drawn significant attention because it is the first study to test topical dutasteride alone, without microneedling. The results appear impressive: all topical doses improved hair parameters versus placebo, showed minimal impact on serum DHT (suggesting good scalp localization), and 1 ml daily of 0.05% topical dutasteride reportedly outperformed oral finasteride in key regrowth metrics.^[31]Panuganti, V. K., Madala, P. K., Grandhi, V. R., Alluri, C. V., Mohammad, J., Kssvv, S. R., & Dundigalla, M. R. (2025). A randomized, double-blind, placebo- and active-controlled phase II study … Continue reading

However, the study reports unusually high baseline hair counts, as well as inconsistencies in the placement and size of the 1 cm² target areas used for serial hair counts. These issues can dramatically skew results, creating the illusion of improvement even when none exists. Real-world data from users of low-dose topical dutasteride (0.01–0.02% applied daily or near-daily) also paint a more modest picture: good localization and serum DHT stability, but primarily maintenance rather than regrowth exceeding oral finasteride

For more information on the emerging potential of topical dutasteride formulations, read our article here.

Oral Finasteride (Evidence Quality – 99%)

As you can see from our evidence quality score, oral finasteride remains the most clinically validated pharmacological treatment for AGA. It acts as a selective inhibitor of the Type II 5AR enzyme, reducing systemic and scalp DHT levels by approximately 60–70%.^[32]Drake, L., Hordinsky, M., Fiedler, V., Swinehart, J., Unger, W. P., Cotterill, P. C., Thiboutot, D. M., Lowe, N., Jacobson, C., Whiting, D., Stieglitz, S., Kraus, S. J., Griffin, E. I., Weiss, D., … Continue reading This substantial suppression slows or halts follicular miniaturization, prolongs the growth (anagen) phase, and enables partial regrowth in many users. The standard 1 mg daily dose for AGA has been extensively studied and represents the optimal balance between efficacy and safety for most men.

Clinical trials have consistently confirmed the effectiveness of finasteride in both the short and long term. A 4-year, randomized study found that 1 mg of finasteride led to increased hair weight (46% vs placebo) and hair count (20% vs. placebo).^[33]Price, V. H., Menefee, E., Sanchez, M., & Kaufman, K. D. (2006). Changes in hair weight in men with androgenetic alopecia after treatment with finasteride (1 mg daily): three- and 4-year results. … Continue reading

You can find an in-depth overview of the clinical studies on finasteride here.

While highly effective, oral finasteride is not without potential drawbacks. A small percentage of users report side effects related to sexual function, including reduced libido, erectile difficulty, and diminished ejaculate volume. Most of these effects are mild and resolve upon discontinuation, although persistent symptoms have been reported in rare cases. Some users also report changes in mood or motivation, likely reflecting individual hormonal sensitivity. For those wishing to minimize systemic exposure, transitioning to topical finasteride or titrating to a lower dose (e.g., 0.25-0.5 mg daily) may be a suitable option.^[34]Gupta, A. K., Venkataraman, M., Talukder, M., & Bamimore, M. A. (2022). Finasteride for hair loss: a review. Journal of Dermatological Treatment. 33(4). 1938-1946. Available at: … Continue reading

There have also been reports of a condition that’s been named ‘post-finasteride syndrome’. While not widely accepted by the medical community, similar symptoms have been reported in a number of individuals who are taking finasteride. These symptoms can include sexual dysfunction, such as loss of libido and erectile dysfunction, neuropsychiatric symptoms like depression and anxiety, and physical changes like muscle atrophy and fatigue. Importantly, there have been cases where these symptoms have persisted after users have stopped taking the drug.

While the authors who published the original article on post-finasteride syndrome do highlight the lack of consistent evidence for persistent side effects found in clinical trials, they suggest that finasteride may act to worsen symptoms associated with sexual dysfunction and psychiatric conditions for some users who already have these issues.^[35]Pereira, A. F. J. R., & Coelho, T. O. A. (2020). Post-finasteride syndrome. Anais Brasileiros de Dermatologia. 95(3). 271-277. Available at: https://doi.org/10.1016/j.abd.2020.02.001

Overall, oral finasteride remains the gold standard for DHT suppression, providing robust and predictable results when used consistently. It’s also important to consider the potential side effects when choosing to take finasteride, and consult with your doctor if symptoms arise.

Honourable Mention – Pyrilutamide

Pyrilutamide (KX-826)

Pyrilutamide takes a different approach to androgen modulation. Rather than reducing DHT production, it acts as a topical androgen receptor antagonist, blocking DHT and testosterone from binding to their receptors in the follicle. By interfering with receptor activation, pyrilutamide aims to suppress the downstream gene expression that leads to follicular miniaturization.^[36]Koralewicz, M. M., & Szatkowska, O. A. (2024, July). Topical solutions for androgenetic alopecia: evaluating efficacy and safety. Forum Dermatologicum. 10(3). 61-70. Available at: … Continue reading

Clinical data show encouraging signals. Trials conducted in China and the United States suggest that topical formulations applied once or twice daily can produce measurable increases in hair counts over several months. Reported side effects are primarily mild local dermatitis, and systemic exposure appears very low. However, many of these results remain unpublished in peer-reviewed journals and have failed to demonstrate statistical superiority over placebo for some measurements.^[37]Kintor Pharmaceuticals. (2022). Developing Novel Drugs and Commercialization Platform. Available at: … Continue reading,^[38]Kintor Pharmaceutical Limited. (2023, March 28). Kintor Pharma Announces Completion of Subject Enrollment in Phase III Clinical Trial for KX-826 for Treatment of Male Androgenetic Alopecia in China. … Continue reading Because these reports have not been published in peer-reviewed journals, they can only currently be considered pre-releases, rather than academic papers. The absence of published, peer-reviewed, blinded, controlled data means that we can’t draw firm conclusions on pyrilutamide, even in the wake of the many press releases that Kintor has published.

To learn more about the research on Pyrilutamide and when to be cautious of press-release-style publications, read our in-depth article.  

For now, pyrilutamide should be viewed as an experimental therapy. Its mechanism is compelling and localized, offering a theoretical advantage over systemic antiandrogens. Still, robust, peer-reviewed clinical trials confirming efficacy and long-term safety are needed before it can be considered a mainstream treatment. Those interested in exploring it should do so only under medical supervision or within the context of formal clinical research.

Final Thoughts

DHT blockers span a broad spectrum, ranging from gentle, naturally derived modulators like pumpkin seed oil and EGCG to powerful prescription therapies such as finasteride and dutasteride. Natural options may improve scalp health and have a modest influence on hormonal activity, but their effects are typically gradual and limited. In contrast, pharmacological inhibitors act directly on the enzymatic pathways responsible for DHT synthesis, offering stronger and more predictable outcomes. Topical finasteride has emerged as a compelling middle ground, delivering scalp-level efficacy with minimal systemic impact, while dutasteride represents the upper limit of potency for those requiring more aggressive intervention.

Ultimately, the “best” DHT blocker depends on individual tolerance, goals, and the stage of hair loss. A well-balanced regimen typically combines a DHT inhibitor with a growth stimulant, such as minoxidil, alongside scalp care and lifestyle modifications. With consistent use and proper medical guidance, these approaches can collectively slow, halt, or even reverse the progression of AGA, helping individuals maintain fuller, healthier hair over time.

Oral finasteride is one of the most widely prescribed treatments for androgenic alopecia (AGA). The drug is a type II 5a-reductase inhibitor, which means it helps reduce dihydrotestosterone (DHT) – the major hormone implicated in pattern hair loss.

At the same time, finasteride isn’t the most powerful DHT-reducing drug available. In fact, there’s a drug that can reduce up to 50% more DHT than finasteride. It’s called dutasteride – and for those who are interested in unlocking another level of hair regrowth, it might be the right choice for them.

So, how much hair regrowth can we expect from dutasteride? Does dutasteride outperform finasteride? How does this drug stack up in terms of side effects? And is there anything else we should know before making the “leap” to a more powerful DHT reducer?

This ultimate guide uncovers the answers.

Interestingly, despite dutasteride’s stronger DHT-reducing effects, this drug doesn’t seem to come with an increased risk of cognitive or sexual side effects – at least when compared to finasteride. In fact, some research indicates that dutasteride might be a better option altogether.

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Highlights

• Effort: Low (drug, taken orally, once daily)
• Expectations: Regrowth observed as early as 3 months.
• Regrowth rate: 5-11% in 6 months, depending on the dosage. Some studies suggest that dutasteride leads to twice the hair count increase as finasteride over a six-month timeframe, though it’s unclear whether this is two
• Response rate: 80-95%, depending on the dosage.
• Cost: $14-$160 per month.
• Problems: Results contingent upon lifelong use; if taken at higher dosages and for long periods, DHT may remain suppressed 6+ months after stopping treatment; risk of side effects similar to finasteride

Key Takeaways

Dutasteride is a drug used most commonly in the treatment of benign prostate hyperplasia. But it’s also used off-label as a treatment for male pattern hair loss.

Dutasteride is a dual 5α-reductase inhibitor, meaning that the drug inhibits both the type I and type II isoforms of the 5α-reductase enzyme. This makes it unique from finasteride, a drug that only inhibits type II 5-alpha reductase. And since dutasteride inhibits more 5-alpha reductase, it can reduce DHT levels much more effectively than finasteride. Specifically, dutasteride appears to reduce systemic DHT levels by 92-96% and scalp DHT levels by 51-79%; whereas finasteride reduces systemic DHT by 60-70% and scalp DHT by 50-60%.

When it comes to hair regrowth, short-term studies suggest that dutasteride is anywhere from 2-5 times more effective than finasteride (depending on the dose). However, the studies comparing dutasteride and finasteride are generally over six-month periods. This may not make for a fair comparison, as finasteride tends to take two years to achieve its full effect.

Despite being more effective, dutasteride doesn’t seem to come with an increased risk of side effects relative to finasteride. In fact, in some instances, dutasteride’s risk of side effects is actually lower than that of finasteride… despite a more substantial decrease in systemic DHT. While it’s debated why this is the case, one explanation might involve dutasteride’s molecular weight, which is much heavier than finasteride, so much so that the drug cannot likely cross the blood-brain barrier.

If you opt for dutasteride, research suggests that for treating pattern hair loss, a dosage of 0.5 mg daily is best. At this dose, dutasteride seems to outperform finasteride and not result in long-term DHT suppression after stopping the medication. At higher dosages (i.e., 2.5 mg daily), DHT can remain suppressed for 6+ even after stopping treatment.

What is dutasteride?

Dutasteride is a drug used to treat a variety of androgen-related problems in men. It’s branded as Avodart®, and it’s most commonly prescribed for the treatment of benign prostate hyperplasia (BPH). But since it’s such a powerful DHT-reducing drug, many doctors will prescribe it “off-label” to treat male pattern hair loss, or androgenic alopecia (AGA).

How does dutasteride reduce DHT?

There are dozens of ways to reduce DHT levels – from lowering overall testosterone to inhibiting enzymes to blocking androgen receptors to increasing DHT metabolism (to name just a few). Some of these methods are safe; some of them are dangerous; some of them aren’t studied well enough in humans to consider trying.

The good news? Dutasteride reduces DHT through one of the better studied (and safer) ways… and similarly to finasteride. It inhibits the enzyme that converts testosterone into DHT: the 5-alpha reductase enzyme.

What makes dutasteride unique? It reduces type I and type II 5-alpha reductase

Dutasteride differs from finasteride in one key way: it reduces more DHT than finasteride. This is because dutasteride inhibits both type I and type II 5-alpha reductase, whereas finasteride inhibits only the type II 5-alpha reductase enzyme.

Both isoforms of 5-alpha reductase – type I and type II – help convert free testosterone into DHT. However, both function at different pH levels, and both are found in different tissue locations throughout the body:^[1]Gerst, C., Dalko, M., Pichaud, P., Galey, J.B., Buan, B., Bernard, B.A. (2002). Type-1 steroid 5 alpha-reductase is functionally active in the hair follicle as evidenced by new selective inhibitors … Continue reading

• Type I 5-alpha reductase is found in the skin, liver, and in three specific places in the hair follicle: the outer root sheath, the dermal papilla, and the matrix cells (a.k.a the cells that produce the hair shaft).
• Type II 5-alpha reductase is predominantly located in the prostate, genital skin, seminal vesicles, epididymis, and liver. But it’s also found in hair follicles.

When it comes to skin tissues near and within hair follicles, the type I isoform dominates… at least in terms of the quantity of enzymes present. But interestingly, it’s the type II isoform that tends to get all of the attention when it comes to male pattern hair loss (AGA).

This is because type II 5-alpha reductase activity in the scalp seems to be a prerequisite for male AGA. This was confirmed back in the 1970s, when studies showed that men born without the genes that make type II 5-alpha reductase also never lose their hair to AGA later in life.^[2]Imperato-McGinley, J., Miller, M., Wilson, J.D., Peterson, R.E., Shackleton, C., Gajdusek, D.C. (1991). A cluster of male pseudohermaphrodites with 5-alpha-reductase deficiency in Papua New Guinea. … Continue reading

In fact, these studies were what built the basis for finasteride – a drug that is now the most popular (and most studied) FDA-approved treatment for AGA. After all, finasteride is a type II 5a-reductase inhibitor, and it’s this specific enzyme that seems directly implicated in DHT-related hair follicle miniaturization.

Dutasteride does the exact same thing as finasteride – except it also inhibits both the type I and type II isoforms of 5-alpha reductase. And, since the body’s total DHT levels are closely linked to the sum of type I and type II isoform activity, dutasteride can technically reduce more DHT than finasteride – around 50% more (depending on the tissue being measured).

If dutasteride also inhibits the type I isoform and reduces more DHT, is it also better than finasteride at regrowing hair?

Maybe.

Several studies have demonstrated that dutasteride reduces DHT levels more than finasteride– at least in tests done on serum (i.e., blood) levels of DHT.^[3]Bramson, H.M., Hermann, D., Batchelor, K.W., Lee, F.W., James, M.K., Frye, S.V. (1997). Unique preclinical characteristics of GG745, a potent dual inhibitor of 5AR. The Journal of pharmacology and … Continue reading In fact, a study found that while finasteride reduces serum DHT levels by ~70%, dutasteride reduces them by ~90% (depending on the dose):^[4]Clark, R.V., Hermann, D.J., Cunningham, G.R., Wilson, T.H., Morrill, B.B., Hobbs, S. (2004). Marked Suppression of Dihydrotestosterone in Men with Benign Prostatic Hyperplasia by Dutasteride, a Dual … Continue reading

But do these results also hold for scalp DHT – the region where DHT reduction matters most?

At least so far, the data suggests yes. Scalp biopsy studies on men taking dutasteride versus finasteride show that at certain dosages, dutasteride reduces much more DHT.^[6]Olsen, E.A., Hordinsky, M., Whiting, D., Stough, D., Hobbs, S., Ellis, M.L., Wilson, T., Rittmaster, R.S., Dutasteride Alopecia Research Team. (2006). The importance of dual 5alpha-reductase … Continue reading

Again, this makes logical sense. After all, type I and type II 5-alpha reductase are found inside and surrounding our hair follicles. And since dutasteride reduces both of these enzymes, this drug should technically reduce more scalp DHT than finasteride.

Thus, it’s totally rational to presume that since:

1. DHT is causally linked to pattern hair loss, and…
2. Finasteride helps treat pattern hair loss by reducing DHT, and…
3. Dutasteride technically reduces more overall DHT + scalp DHT than finasteride…

Then all else equal, dutasteride should be a more effective hair loss drug.

But is this what the clinical research suggests? In order to answer this question, we’ll need to evaluate dutasteride’s hair-regrowing abilities against its risk profile: its reports of side effects, and how this does (or doesn’t) differ from finasteride.

Dutasteride versus finasteride: clinical trials (hair regrowth)

While there have been a handful of studies that have researched dutasteride, there are only four studies that provide data relevant to this question. We’ve compiled these studies as well as their methodologies, results, and conclusions into the chart below.

Studies Comparing the Effectiveness of Dutasteride and Finasteride
	High quality study?	Daily dosages used	Length of study	Average hair count changes with dutasteride (%)	Average hair count changes with finasteride (%)	Any other notable results?	Superior treatment?
Study #1.[7]Olsen, E.A., Hordinsky, M., Whiting, D., Stough, D., Hobbs, S., Ellis, M.L., Wilson, T., Rittmaster, R.S., Dutasteride Alopecia Research Team. (2006). The importance of dual 5alpha-reductase … Continue reading	Yes, randomized, placebo-controlled	Dutasteride: 0.1 mg, 0.5 mg, 2.5 mg Finasteride: 5 mg	24 weeks	0.1 mg: 8.6% 0.5 mg: 10.1% 2.5 mg: 11.3%	8.3%	The amount of patients who achieved at least 10% increase in hair count increases with dutasteride dose. In other words, as dose increased, so did the amount of patients who achieved at least 10% increase in density	Dutasteride 0.5 mg and 2.5 mg
Study #2.[8]Shanshanwal, S.J.S., Dhurat, R.S. (2017). Superiority of dutasteride over finasteride in hair regrowth and reversal of miniaturization in men with androgenetic alopecia: A randomized controlled … Continue reading	Yes, randomized controlled trial	Dutasteride: 0.5 mg Finasteride: 1 mg	24 weeks	11%	2%	24% increase in the number of thick, terminal hairs with dutasteride vs. 4% with finasteride	Dutasteride
Study #3.[9]Harcha, W.G., Martinez, B.J., Tsai, T-F., Katsuoka, K., Kawashima, M., Tsuboi, R., Barnes, A., Ferron-Brady, G., Chetty, D. (2014). A randomized, active- and placebo-controlled study of the efficacy … Continue reading	Yes, randomized, placebo-controlled trial	Dutasteride: 0.02 mg 0.1 mg 0.5 mg Finasteride: 1 mg	24 weeks	0.02 mg: 2.3% 0.1 mg: 8% 0.5 mg: 11.7%	7.5%	0.5 mg dosage of dutasteride was superior to 1mg finasteride in increasing hair thickness.	Dutasteride at 0.5 mg
Study #4.[10]Choi, G-S., Sim, W-Y., Kang, H., Huh, C.H., Lee, Y.W., Shantakumar, S., Ho, Y-F., Oh, E-J., Duh, M.S., Cheng, W.Y., Bobbili, P., Thompson-Leduc, P., Ong, G. (2022). Long-Term Effectiveness and Safety … Continue reading	Yes, multicenter long-term retrospective study	Dutasteride: 0.5 mg/day  Finasteride: 1 mg/day	≥3 years (mean 3.4 years)	Hair count data not reported (too sparse; BASP classification used instead)	N/A	Dutasteride is significantly superior across BASP basic, basic M, and V types.	Dutasteride

Here’s what these results tell us about dutasteride:

1. Dutasteride, at a dosage of 0.5 mg, has a clear advantage over both 1 mg and 5 mg of finasteride over the course of 24 weeks.
2. Much like finasteride, a higher dose doesn’t necessarily equal better results. In fact, among two different studies, a 2.5 mg dose showed no better efficacy over a 0.5 mg dose. However, a higher dose appears to increase the number of users who will achieve at least a 10% increase in density.
3. Dutasteride doesn’t just increase the number of hairs present; it also seems to increase the thickness of existing hairs, and more effectively than finasteride. This suggests that dutasteride may be a better drug for reversing hair follicle miniaturization.

The most interesting finding, though? Despite the fact that 2.5 mg of dutasteride reduces scalp DHT by almost 30% more than 0.5 mg, this doesn’t necessarily translate to more hair regrowth. In fact, the difference in efficacy between the two doses doesn’t even reach statistical significance.

This suggests that even when we reduce DHT to a greater degree and where it’s most important (the scalp), we don’t necessarily see evidence that this increases efficacy. In other words, maybe reductions to scalp DHT don’t always correlate to increased hair regrowth. Maybe there is a degree of pattern hair loss that stems directly from serum DHT, not just scalp DHT. Dr. George Cotsarelis (of PGD2 fame) has mentioned this before in interviews. Hopefully, with more research, we’ll have a clearer answer.

Nonetheless, these trials still tell us that dutasteride, at various doses, is more effective than finasteride – and anywhere between 2- and 5-fold more effective (depending on the doses).

The problem with these trials? Many are relatively short (24 weeks)

The one caveat to all but one of these comparative studies is that they were conducted over a 24-week period. This makes it difficult to discern just how effective dutasteride versus finasteride is… mainly because finasteride is notoriously slow at regrowing hair.

For instance, studies show that men taking finasteride generally just start to see improvements around the 3-6 month mark.^[11]Price, V.H., Menefee, E., Sanchez, M., Ruane, P., Kaufman, K.D. (2002). Changes in hair weight and hair count in men with androgenetic alopecia after treatment with finasteride, 1 mg, daily. Journal … Continue reading These studies also show that finasteride takes 2+ years to take full effect on our hair, with scalp hair counts increasing an average of 10% over this two-year period before plateauing.

That’s 96 weeks for finasteride to demonstrate full efficacy, not 24 weeks – the length of time for all studies comparing dutasteride to finasteride. If, for unforeseen reasons, dutasteride efficacy plateaus after six months, then maybe finasteride catches up in the long run. If dutasteride continues its trajectory at the same pace as finasteride, then maybe it’s actually 2- to 5-times more effective than finasteride… and we just don’t know it yet.

In any case, we can surmise that:

1. Dutasteride works faster than finasteride. Meaning, both will achieve similar density gains, but dutasteride can achieve this in about a quarter of the time.
2. It’s very possible (and probable) that dutasteride increases hair counts by even more over a longer period of time. In other words, if we studied dutasteride for the same amount of time as finasteride, there’s a chance it might be more effective. This is further demonstrated by members here who’ve switched from finasteride (after 5+ years of use) to dutasteride, and within months, saw even bigger hair gains (see CradleCap’s case study).

Regardless, there’s still one piece to the puzzle we haven’t examined yet: the incidence of side effects.

After all, if dutasteride is 200%-500% more effective than finasteride, but it also comes with a 200-500% increase in side effects… that may defeat the point of using it. After all, for those dealing with hair loss, we’re always trying to find treatments that strike the right balance between effectiveness versus the risk of side effects.

This begs the question: given that dutasteride reduces more DHT and seems much more effective than finasteride, does it also come with an increased risk of side effects?

The answers might surprise you.

Is there an increased risk of side effects with dutasteride?

We already know that dutasteride reduces serum DHT by larger amounts than finasteride. So, does this come with a higher risk of sexual side effects?

Several studies have attempted to answer this question. Here’s what they have to say:

Incidence of Side Effects
	Average incidence of total side effects among dutasteride group vs. finasteride group	Decreased libido (%)	Ejaculation disorders (%)	Erectile dysfunction (%)	Breast enlargement (%)	Breast tenderness (%)	Total serum DHT reduction
Study #1	4.6% vs. 2.6%	Dutasteride 0.1 mg: 3% 0.5 mg: 1% 2.5 mg: 13% Finasteride 5 mg: 4%	Dutasteride 0.1 mg: 4% 0.5 mg: 1% 2.5 mg: 1% Finasteride 5 mg: 3%	Dutasteride 0.1 mg: 0% 0.5 mg: 0% 2.5 mg: 0% Finasteride 5 mg: 1%	N/A	N/A	Dutasteride 0.1 mg: 69.8% 0.5 mg: 92% 2.5 mg: 96.4% Finasteride 5 mg: 73%
Study #2	10% vs 10%	N/A	N/A	N/A	N/A	N/A	N/A
Study #3	11.5% vs. 13.4%	Dutasteride 0.02 mg: 8.1% 0.1 mg: 6.9% 0.5 mg: 4.9% Finasteride 1 mg: 6.7%	Dutasteride 0.02 mg: 2.2% 0.1 mg: 4.8% 0.5 mg: 3.3% Finasteride 1 mg: 3.9%	Dutasteride 0.02 mg: 4.3% 0.1 mg: 3.7% 0.5 mg: 5.4% Finasteride 1 mg: 5.6%	Dutasteride 0.02 mg: 0% 0.1 mg: 0.5% 0.5 mg: 0.5% Finasteride 1 mg: 0.6%	Dutasteride 0.02 mg: 0.5% 0.1 mg: 0.5% 0.5 mg: 0% Finasteride 1 mg: 0%	N/A
Study #4	7.6% vs. 10.5%	Dutasteride: 1.2%  Finasteride: 0.7%	N/A	Dutasteride: 0.4%  Finasteride 0%	N/A	N/A	N/A

When we examine this data, here’s what we find:

• In one study, 0.5 mg and 2.5 mg of dutasteride reduced serum DHT by 19% and 23% more than finasteride, respectively. Despite this, finasteride still had a higher incidence of side effects than the various doses of dutasteride in some categories (except for the incidence of decreased libido, which appeared to affect about 13% of men in the 2.5mg group). In all other categories, the incidence of side effects was virtually the same.
• Side effects associated with dutasteride don’t appear to follow a dose-response relationship (at least in these three studies). In fact, in studies #1 and #2, a higher incidence of side effects is observed in the lowest In other words, it appears that higher doses don’t necessarily mean a higher risk of side effects.
• Overall, if we average out the total incidence of side effects over the three studies, finasteride and dutasteride have the exact same incidence of side effects: 8.7% for dutasteride and 8.6% for finasteride.
• The conclusion? Dutasteride is more effective at increasing hair counts over a 6-month period, all without a higher risk of side effects.

Moreover, here are some other findings from these studies that are not reported within that table:

• The most common side effect was observed in study #1’s 2.5 mg dutasteride group – about 13% reported decreased libido. What the table doesn’t tell you is that more than half of the men reporting decreased libido also reported that it spontaneously resolved over the course of the study. In other words, it resolved even while taking dutasteride. Moreover, an additional 22% reported libido recovery after cessation of use.
• For men reporting side effects with dutasteride, almost all of these men reported resolution while still taking dutasteride.
• In contrast, men taking finasteride did not see a resolution of side effects during treatment. Most did, however, report resolution after the study was over.

Again, these side effects are only derived from clinical trials conducted over the course of 6 months. So, these studies alone don’t really tell us what might happen over longer periods of use. And considering that, much like finasteride, dutasteride likely has to be taken for a lifetime to sustain its effectiveness – this really matters.

So, is there any insight as to what the incidence of side effects might be after 6 months?

Well, when we examine the research, we find that the incidence of side effects actually decrease over time with dutasteride use. For example, one four-year trial employing a daily 0.5 mg dose demonstrated that the incidence of side effects decreased from 6% in year one to a marginal 0.4% by year four.

We could argue that this shift is simply a consequence of our olfactory wiring + change blindness – whereby we have a tendency to only notice changes (i.e., new smells) when they first arrive, and whereby if changes occur too slowly, we generally won’t notice them at all.

At the same time, we could also argue that with long-term use of dutasteride, our bodies simply rewire and find ways for testosterone (and other hormones) to replace the roles previously fulfilled by DHT. This is generally how the body works – there are dozens of “fallback” mechanisms in case a vitamin, mineral, or hormone is missing. In other words, we’re more durable than we think.

Why does dutasteride come with an equivalent (or lower) risk of side effects?

It’s puzzling that dutasteride seems to come with an equivalent (or lower) risk of side effects… and that over time, these side effects seem to decrease more than with finasteride. This is in spite of dutasteride reducing much more DHT than finasteride. What could explain these paradoxical findings?

Well, one could argue that maybe DHT reduction isn’t necessarily as great of a predictor of side effects as we think. But, there is one additional explanation for these findings, and one that’s much more interesting to explore…

It’s the actual structure of the dutasteride molecule itself… and the fact that the size of this molecule might greatly reduce the drug’s accessibility to certain organs within our body. Specifically, the brain.

Why might the molecular characteristics of dutasteride influence the risk of side effects?

The blood is the ultimate transporter for nutrition. It’s also the transporter for oral drugs.

During circulation, the blood will deposit various compounds into cells, where they then elicit their specific effects. However, in the brain, it isn’t quite as simple. This is because of a membrane called the blood-brain barrier (BBB).

This membrane is comprised of cells that maintain tight cellular junctions. In other words, these cells are packed in close together with minimal space between each cell. As such, only very small compounds or compounds that can bind to specific entry receptors on the BBB can pass through the membrane into the brain.

In terms of molecular size, a given compound has to be smaller than 400 daltons (a measurement of mass) to traverse past this membrane. If any larger? The compounds cannot theoretically enter the brain through blood transportation. Therefore, these molecules may not be able to elicit their specific effects on the brain.

So, what does this have to do with dutasteride and finasteride? And why might this explain the difference in the incidence of side effects?

Interestingly, while both finasteride and dutasteride act similarly with respect to DHT reduction, they are actually quite different on a molecular level – particularly regarding their molecular weight.

While finasteride is only 372 daltons, dutasteride is 528 daltons.

The biggest difference here? Finasteride is small enough to pass through the tight junctions of the blood-brain barrier (BBB). Dutasteride isn’t.

As such, finasteride may elicit effects on the brain itself, which may precipitate major effects on sexual and mental side effects. In contrast, dutasteride may have less of a direct effect on the brain… or a reduced capacity to effect androgen metabolism in the brain relative to finasteride.

Again, this is all hypothetical, and the science is still very much debated. For instance, this study on mice found that dutasteride does influence androgen metabolism in the brain (although that study also found that dutasteride had neuroprotective effects on mice, helping to stave off Parkinsons).^[12]Litim, N., Morissette, M., Caruso, D., Melcangi, R.C., Di Paolo, T. (2017). Effect of the 5α-reductase enzyme inhibitor dutasteride in the brain of intact and Parkinsonian mice. The Journal of … Continue reading

At the same time, with dutasteride use, some reduction in brain androgen activity is technically to be expected… even if dutasteride doesn’t technically enter the brain. Why? Because 5-alpha reductase can be transported via the blood (where dutasteride does elicit an effect). And if blood entering the brain has less 5-alpha reductase activity, then this would also change androgen activity in the tissues where that blood eventually gets transported (i.e., the brain).

In any case, our suggestion here is that dutasteride itself has a harder time entering into brain tissues, and that this is why it may confer to a lower risk of side effects (despite more DHT reduction) than finasteride.

So, despite the fact that dutasteride has a more powerful effect on both systemic DHT than finasteride, the lower or on-par incidence of side effects may simply be due to dutasteride’s molecular weight… and how this dampens the drug’s ability to enter brain tissue.

Thus, it appears we can derive faster, more substantial hair regrowth in AGA… all with the same or even lower risk of side effects. Moreover, we can even leverage dosages to both maximize regrowth and minimize the risk of side effects.

Dutasteride: best candidates + best practices (i.e., dosages)

It goes without saying that dutasteride is a drug that is appropriate only for one specific kind of hair loss: androgenic alopecia (pattern hair loss). It also goes without saying that this drug is studied almost exclusively on men. Therefore, men with pattern hair loss are the best candidates.

So, for men with pattern hair loss, what’s the best dose?

Well, revisiting data from the three studies comparing dutasteride to finasteride, we see that larger doses of dutasteride are generally no more effective than a dosage of 0.5 mg. And based on the safety data, this appears to be one of the safest doses, too.

Specifically, the studies show that 0.5 mg can increase hair counts by anywhere between 10 and 11.5% in 6 months, with just a 1.3% overall risk of sexual side effects. In contrast, finasteride’s risk of side effects ranges from 2-13% with regrowth rates only around 7-8%.

So, a daily dose of 0.5 mg of dutasteride orally seems to both maximize hair regrowth and minimize the risk of side effects. Moreover, it does so in a safer and more effective manner than both 1 mg and 5 mg doses of finasteride.

Finally, a 0.5 mg daily dose is also a dose that allows for our DHT levels to bounce back within six months after stopping the drug. Because of dutasteride’s longer half-life, it tends to exert a longer effect in the body. At higher dosages, it seems as though DHT levels remain suppressed for the majority of users, at least for six months of quitting. A 0.5 mg daily dose prevents this from happening, allowing DHT to return to 80% of baseline levels after six months of cessation, and likely 100% baseline levels a few months thereafter.

Want an example of a long-term dutasteride user? See Ashton Kutcher.

If you’d like an example of a long-term dutasteride user, look no further than Ashton Kutcher.^[13]Team Coco. (2018). Ashton Kutcher’s Hair Is Starting To Go | CONAN on TBS. Available at: https://www.youtube.com/watch?v=Wv9gu1zJdRo (Accessed: November 2025)

During his 2018 interview with Konan, he revealed that he had used the drug for years, only hopping off to father his children (born in 2014 and 2016). It seems to have worked wonderfully for him. Just look at his hairline in 1998 versus today. While there’s no information about whether he has returned to using dutasteride, it also doesn’t seem like his hairline has changed much over the past several years anyway.

Summary

Finasteride is one of the most powerful and frequently used therapies for AGA. However, emerging research indicates that dutasteride may have a clear advantage over finasteride, at least in terms of (1) scalp DHT reduction, (2) hair regrowth, and (3) side effects.

Specifically, a 0.5 mg daily dose appears to increase hair density by anywhere between 10 and 11.5% over the course of 6 months, which happens to be the hair count increase expected from 2+ years of finasteride use. Moreover, dutasteride seems to achieve this without greatly increasing someone’s risk of cognitive or sexual side effects. In fact, the incidence of side effects with dutasteride seems to decrease over time, with one study demonstrating just a 0.4% incidence of side effects with four years of use.

While higher doses (up to 2.5 mg) do increase the response rate to the treatment, they don’t appear to increase the average amount of hair someone regrows. Moreover, they also increase the likelihood of long-term DHT suppression post-treatment. As such, a 0.5 mg daily dose seems like the best approach when utilizing this drug for hair regrowth.

Considering these overall advantages, cost-effectiveness, and accessibility, dutasteride shows considerable promise for men with AGA.

If you’re interested in taking dutasteride or swapping out your oral finasteride, talk with your doctor about the research. If you’re a good candidate for the drug, ask them to prescribe you a 0.5 mg daily dose, and please keep us posted with your results!

Dutasteride is one of the strongest off-label treatments for androgenic alopecia. In this guide, we’ll explore the evidence supporting two delivery methods for dutasteride: topical dutasteride and mesotherapy dutasteride. We’ll also provide clear step-by-step instructions for anyone looking to try these therapies at home or find clinicians willing to do the procedures.

Overview: Topical / Mesotherapy Dutasteride

• Effort: Low (once weekly-to-monthly applications, depending on topical or mesotherapy delivery).
• Expectations: Hair improvements within 4-6 months.
• Response rate (i.e., the percent of people who experience a slowing, stopping, or partial reversal of AGA):
  • Topical dutasteride: 70-90%
  • Topical dutasteride + microneedling: 60-80%
  • Mesotherapy dutasteride: 60-80%
• Regrowth rates (i.e., the percent change to hair counts, hair diameters, and hair density (i.e., ∆hair counts x ∆hair diameters)):
  • Topical dutasteride: +23-25% increase in hair counts (mean +75 hairs/cm² vs baseline in the 0.05% group over 24 weeks).
  • Topical dutasteride + microneedling: 10-15% increase in hair counts, 15-20% increase in hair density (sometimes more)
  • Mesotherapy dutasteride: 10-15% increase in hair counts, 15-20% increase in hair density (sometimes more)
• Advantages: Easy to administer; works for the majority of people; minimizes DHT reductions elsewhere in the body; likely confers with a lower side effect profile.
• Disadvantages: Clinical studies are of lower quality; no standardization across mesotherapy needle depths or dutasteride exposure volumes per session; high variability between patients regarding systemic absorptions puts the onus on each patient to test serum DHT levels before/during treatment; expensive.

Interested in Topical Dutasteride?

Hair gains bigger than finasteride? Dutasteride makes this possible, if prescribed*

Take the next step in your hair regrowth journey. Get started today with a provider who can prescribe a topical solution tailored for you.

Click Here For 15% Off

*Only available in the U.S. Prescriptions not guaranteed. Restrictions apply. Off-label products are not endorsed by the FDA.

Key Takeaways

• The Good News:
  • Topical / mesotherapy dutasteride works. While the evidence is limited and of lower quality, multiple studies from different research groups all suggest that topical dutasteride and mesotherapy dutasteride improve hair loss outcomes for men and women with androgenic alopecia.
  • Topical / mesotherapy dutasteride may minimize unwanted declines in serum DHT. Multiple studies (while not perfectly designed) suggest, when dosing is done properly, that topical dutasteride and/or mesotherapy dutasteride can improve hair parameters while only modestly reducing serum DHT levels (a marker for systemic absorption). This has been confirmed by members here who’ve done serum DHT tests before/after treatment and seen only 10-15% declines in DHT. Moreover, absorption studies testing 1 mL of 0.025% topical dutasteride (i.e., 0.25 mg) applied to the scalp show, after 12 hours, that ~7% of the drug enters the bloodstream while 25% of the drug remains within the dermis of the scalp. This means that within proper exposure volumes, we can maximize DHT reduction in the scalp while minimizing the effects of DHT reduction elsewhere in the body.
  • No sexual side effects (yet) reported in the clinical data. While the currently available studies have small sample sizes, all investigations on topical / mesotherapy dutasteride have yet to have a participant report sexual side effects. This experience is echoed by members here who’ve adhered to the usage ad frequency parameters of both topical and mesotherapy dutasteride.
• Critical Unknowns:
  • How does topical dutasteride and mesotherapy dutasteride compare to each other (and other therapies)? Due to lacking head-to-head clinical studies, we don’t yet have an answer. However, directional hair count data across studies suggest that topical / mesotherapy dutasteride is probably less powerful than its oral counterpart. (This comparison is unscientific, but it’s all we can currently glean.)
  • What’s the best dosage, frequency of application, and carrier agents? While low-exposure volumes of topical / mesotherapy dutasteride show minimal effects on serum DHT, we don’t yet know the perfect dosing schedule to maximize hair regrowth while minimizing serum DHT reductions. It’s likely that leakage from the scalp and systemic absorption vary depending on the individual and the treatment methodologies: age, genetics, mode of delivery, dosage per application, application frequency, and application volume are just a few of the dozens of factors impacting the answers to these questions.
  • How does topical dutasteride perform as a standalone therapy? Early data suggest that low-dose topical dutasteride (including 0.05%) can improve hair parameters and may, in some trials, appear comparable or even superior to oral finasteride, but methodological limitations and conflicting real-world experiences mean these findings should be interpreted cautiously until independently replicated.
•  Best Practices & Recommendations
  • See below.

Key Recommendations

Topical dutasteride and mesotherapy dutasteride are probably most appropriate for people who:

• Have androgenic alopecia
• Don’t want to use oral finasteride or oral dutasteride, but want to leverage a pharmaceutical 5-alpha reductase inhibitor
• Want to better localize the effects of dutasteride to scalp
• Are comfortable experimenting with delivery methods that are lesser explored and have lower levels of clinical support
• Are comfortable investing $50-$400 per month into treatment, depending on the mode of delivery (topical or mesotherapy)
• Don’t have metabolic syndrome (as one study suggested that mesotherapy dutasteride was ineffective for these patients)

Step-By-Step Guide

Topical dutasteride

If trying topical dutasteride:

• Limit topical exposure of dutasteride to 0.1-0.5mg weekly.
  • This can be achieved in many ways. Consider 1 mL formulas more appropriate for localized hair loss, and 2 mL formulas more appropriate for diffuse hair loss (for more spread of liquid). Examples:
    • 1 mL of 0.01% to 0.05% dutasteride, once weekly. Exposure = 0.1-0.5 mg
    • 1 mL of 0.025% dutasteride, twice weekly. Exposure = 0.5 mg
    • 2 mL of 0.005% to 0.025% dutasteride, once weekly. Exposure = 0.1-0.5 mg
    • 2 mL of 0.005% to 0.0125% dutasteride, twice weekly. Exposure = 0.2-0.5 mg
• Leave in scalp for at least 4 hours, and preferably 8-12 hours
  • This will allow 25% of the dutasteride applied to penetrate into the percutaneous tissues, so it can have an effect.
  • This will minimize the amount of dutasteride that enters the bloodstream, thus reducing systemic absorption.
  • The easiest way to do this is to apply topical dutasteride before bed and then wash it out in the morning.
• Consider combining with microneedling
  • If combining with microneedling, do not apply topical dutasteride the day of microneedling
• Consider testing serum DHT levels before/during treatment
  • This will help track if topical dutasteride is remaining localized to the scalp.
  • In tracking DHT levels, you can increase or decrease dutasteride dosing depending on your serum DHT readouts.
• Product recommendations
  • MinoxidilMax: 0.1% topical dutasteride, 60 mL.
    • You can use this solvent to dilute the formula down to 0.005% to 0.02%. If you’d like help with this, ask us. We’re currently building out a “how to” video for diluting topicals that will make this process simple. But if you want to get a jumpstart on this, please don’t hesitate to ask for our help.

Mesotherapy dutasteride

If trying mesotherapy dutasteride:

• Start with mesotherapy injections once monthly.
  • After 6+ months, move to one session every 1-3 months.
  • If once monthly injections are infeasible, opt for injections once every three months.
• Limit dutasteride exposure to 0.1-0.2 mg per session.
  • This is equivalent to 1-2mL of 0.01% dutasteride
• Consider testing serum DHT levels before/during treatment
  • This will help track if topical dutasteride is remaining localized to the scalp.
  • In tracking DHT levels, you can increase or decrease dutasteride dosing depending on your serum DHT readouts.

How do I track down a clinician who can provide mesotherapy dutasteride?

It’s not easy, but it can be done.

Step #1: Build a list of practitioners offering mesotherapy in your locale

Run a google search for dermatologists and/or medical spas in your area. When checking out their websites, make sure they offer mesotherapy. It’s okay if the mesotherapy they offer is not related to hair loss. All that matters is that they offer mesotherapy, because that means they will have a mesotherapy gun in their office.

Track down their names and contact information via contact forms and emails listed on their sites. Try to build a list of 5-10 clinicians within travel distance.

Step #2: Send each practitioner this personalized email

Here’s an email script that has given us some success. Please personalize as necessary:

Dear [CLINICIAN],

My name is [YOUR NAME]. I’m reaching out because I’m interested in trying mesotherapy dutasteride for the treatment of androgenic alopecia. The procedures are typically done once monthly for 6+ months. I wanted to see if your offices would be willing to provide the therapy to me.

I’ve been encouraged by the results of this mini-review, suggesting that repeated mesotherapy dutasteride may improve hair loss outcomes for men with androgenic alopecia, and without significantly altering serum DHT levels.^[1]Herz-Ruelas, M.E., Alvarez-Villalobos, N.A., Millan-Alanis, J.M., de Leon-Gutierrez, H., Ocampo-Garza, S.S., Grimalt, R. (2020). Efficacy of Intralesional and Oral Dutasteride in the Treatment of … Continue reading I’m planning on tracking serum DHT before/during treatment, and I’d be happy to share the blood work with you (especially as interest in this therapy is growing, it might be nice to have the data).

I’m happy to source the mesotherapy dutasteride serum. All I need is a clinician trained in mesotherapy to administer the procedure. Are you interested? If so, I can come to offices as soon as next week.

All my best,
[YOUR NAME]
[PHONE NUMBER]

Step #3: Secure a practitioner 

Typically, for every 5-10 clinicians who receive the above email, one will respond to say that they’re interested. Meet with these clinicians, print out and share with them the studies, and show them the methodologies (below) to standardize the procedure, thus making it as easy as possible for the doctor to administer.^[2]Herz-Ruelas, M.E., Alvarez-Villalobos, N.A., Millan-Alanis, J.M., de Leon-Gutierrez, H., Ocampo-Garza, S.S., Grimalt, R. (2020). Efficacy of Intralesional and Oral Dutasteride in the Treatment of … Continue reading

Methods For Mesotherapy Dutasteride (With A Clinician):

• Injection depth: intradermal (i.e., between the epidermal and dermal skin layers, roughly 0.5-0.75 mm deep)
• Mesotherapy formulation: 0.01% dutasteride in a 10 mL vial (provider here)
• Injection volume per session: 1-2 mL (i.e., 0.1-0.2 mg of dutasteride)
• Injection frequency: once monthly for six months, then once every 1-3 months thereafter

Can I try mesotherapy at home?

To be clear, we DO NOT recommend taking a DIY approach to mesotherapy. If you cannot find a provider, we recommend trying topical dutasteride + microneedling. Topical dutasteride is far more accessible, and it’s also easily administered at home. It’s also likely that the combination produces similar results to mesotherapy dutasteride.

Under the circumstances that you decide not to heed our warnings, here are DIY instructions for mesotherapy dutasteride.

Methods for Mesotherapy Dutasteride (At-Home):

• Buy this mesotherapy device. Use the 9-needle cartridges and adjust the needle depth to 0.5mm when operating.
• Buy mesotherapy dutasteride from this provider (we lab tested their products; they meet quality and purity standards).
• Follow the instructions from the manufacturer to deliver mesotherapy to your scalp once per month.
• Consider tracking serum DHT levels before/during treatment.

Below is a scientific deep-dive on topical / mesotherapy dutasteride.

What Is Topical Dutasteride and How Does It Work?

Topical dutasteride is topical version of the oral drug, dutasteride. Whereas oral dutasteride tends to have hormonal effects all throughout the body, topical dutasteride is designed to selectively target just the scalp skin – allowing people to reap all the hair-growing benefits of dutasteride, and without the risk of systemic side effects.

At least, that’s the hope.

Specifically, dutasteride lowers the hormone dihydrotestosterone (DHT), which is causally linked to androgenic alopecia. It does so by inhibiting the enzyme that converts testosterone into DHT: 5-alpha reductase.

Dutasteride is one of the most powerful 5-alpha reductase inhibitors available. Whereas hair loss drugs like finasteride inhibit 5-alpha reductase and lower DHT levels by ~70%, dutasteride can lower DHT levels by 95%.

This is because there are three known isoforms of 5-alpha reductase: type I, II, and III. Compared to finasteride, dutasteride is more effective at inhibiting them. In fact, dutasteride is able to target the type I isoform 100x better than finasteride, and the type II isoform 3x better than finasteride.^[3]Zhou, Z., Song, S., Gao, Z., Wu, J., Ma, J., Cui, Y. (2019). The efficacy and safety of dutasteride compared with finasteride in treating men with androgenetic alopecia: a systematic review and … Continue reading

How Does Oral Dutasteride Compare To Oral Finasteride for Androgenic Alopecia?

Dutasteride’s larger effects on DHT reduction also confer better hair regrowth outcomes.

A 2019 meta-analysis by Zhou et al. found that oral dutasteride regrew more hair than oral finasteride – even at dosage ranges lower than 0.5 mg daily.^[4]Zhou, Z., Song, S., Gao, Z., Wu, J., Ma, J., Cui, Y. (2019). The efficacy and safety of dutasteride compared with finasteride in treating men with androgenetic alopecia: a systematic review and … Continue reading And while the studies in this review were relatively short (i.e., 6 months) and had sample sizes of less than 500 participants, it’s hard to ignore the preliminary evidence suggesting that oral dutasteride packs a big punch for hair regrowth – even at dosages as low as 0.1mg daily.

What About Safety?

Despite reducing more DHT and regrowing more hair, both finasteride and dutasteride appear to carry the same risk of side effects.

Why is this? Wouldn’t we expect dutasteride to carry a higher risk of side effects, since it reduces DHT levels more?

Generally, yes. But that’s not currently reflected in the data. Regarding why, there are many hypotheses:

• Biases in sample sizes and study durations. Perhaps dutasteride does carry a larger risk of side effects, as it has been shown to do so in some patient populations (for instance, dutasteride carries a higher risk versus finasteride for gynecomastia in patients with enlarged prostates). But perhaps the sample sizes in these hair loss studies were too small in these studies to pick up the differences. Or, perhaps the studies did not run long enough to capture all risks.^[7]Hagberg, K.W., Divan, H.A., Fang, S.C., Nickel, J.C., Jick, S.S. (2017). Risk of gynecomastia and breast cancer associated with the use of 5-alpha reductase inhibitors for benign prostatic … Continue reading
• Differences in isoform side effect attribution. Perhaps the type II 5-AR enzyme (i.e., the one predominantly targeted by finasteride) is the one isoform predominantly responsible for most of the side effects associated with finasteride and dutasteride. (We’ve heard this argument before, but we don’t necessarily believe it.^[8]Rahimi-Ardabili, B., Pourandarjani, R., Habibollahi, P., Mualeki, A. (2006). Finasteride induced depression: a prospective study. BMC Clinical Pharmacology. 6(7). Available at: … Continue reading
• Tissue-dependent concentration differences of isoforms. For example, in the prostate and testes, the type II isoform is expressed far more than type I. The opposite is true in brain tissue, where type I 5-AR is predominantly found. Perhaps the side effects of 5-AR inhibitors depend on how much 5-AR is inhibited in specific tissues, and at the dosages administered for dutasteride and finasteride, there just isn’t enough difference in DHT reduction to make one drug more likely to produce sexual side effects than the other.^[9]Wang, K., Fan, D-D., Jin, S., Xing, N-Z., Niu, Y-N. (2014). Differential expression of 5-alpha reductase isozymes in the prostate and its clinical implications. Asian Journal of Andrology. 16(2). … Continue reading

Even still, there remains no consensus among clinicians for why this is the case.

Pharmacokinetics

How Does Dutasteride Behave In Our Bodies?

Pharmacokinetics is a term used to describe the behavior of drugs once they enter the body: how quickly they are transported to tissues, how quickly they are metabolized (i.e., their half-life), and more.

Dutasteride and finasteride, despite being structurally similar, differ dramatically in their half-lives. For instance, finasteride has a half-life of 5-8 hours. That means that after ingesting finasteride, it takes 5-8 hours before 50% of that finasteride leaves our bloodstream.

Dutasteride, on the other hand, has a half-life that can last 5+ weeks. In fact, dutasteride’s half-life depends on a lot of factors: age, genetics, and, most importantly, the amount of dutasteride given to an individual at one time.

This was investigated by Gislekog et al. (1998) by giving a dose of dutasteride ranging from 0.01mg to 40mg to 32 healthy males. The findings showed a number of distinctions:

1. The half-life of the drug increases with increasing dose.
2. Serum concentrations of dutasteride can last for quite a while before it is undetectable.

This is presented in the following table:

Dose	Serum Concentration Duration (up to 1ng mL-1)
0.1mg	Approximately one day.
1.0mg	Averaging around seven days, but can be up to 14 days.
2.5mg	Averaging approximately 14-21 days, but can be as long as 28 days.
5.0mg	Approximately 21-28 days.
10.0mg	Greater than 28 days.
20.0mg	Greater than 28 days.
40.0mg	Greater than 28 days.

Oral finasteride has established itself as a highly effective treatment for androgenic alopecia (AGA) and is widely prescribed around the globe. Its success can be largely attributed to its proven ability to slow hair loss and stimulate regrowth by inhibiting the conversion of testosterone to DHT, the hormone chiefly responsible for follicular miniaturization. 

However, despite its well-documented efficacy, oral finasteride has become equally notorious for its potentially systemic side effects. Some men experience adverse effects such as decreased libido, erectile dysfunction, mood changes, and even persistent symptoms after discontinuation, a phenomenon called post-finasteride syndrome.^[1]Diviccaro, S., Melcangi, R.C., Giatti, S. (2019). Post-finasteride syndrome: an emerging clinical problem. Neurobiology of Stress. 12. 100209. Available at: https://doi.org/10.1016/j.ynstr.2019.100209 This reputation has prompted many to seek alternatives that are both effective and safer for long-term use.

Recently, topical finasteride formulations have garnered attention as a promising alternative. By delivering the medication directly to the scalp, topical finasteride aims to minimize systemic absorption and thereby reduce the likelihood of side effects while still providing the benefits of DHT inhibition where it matters most. This alternative approach has piqued the interest of both patients wary of systemic issues and clinicians seeking tailored treatments.

In this article, we will examine whether topical finasteride can serve as a viable alternative to its oral counterpart. The main focus will be on answering three questions:

1. Can topical finasteride effectively regrow hair in those affected by AGA?
2. Does it match the efficacy results seen with oral finasteride?
3. Can it reduce hair loss while offering a more favorable side effect profile?

Ulo offers finasteride options that range from low to high dose finasteride – allowing you to be flexible in your treatment choices.

Interested in Topical Finasteride?

Low-dose & full-strength finasteride available, if prescribed*

Take the next step in your hair regrowth journey. Get started today with a provider who can prescribe a topical solution tailored for you.

Click Here For 15% Off

*Only available in the U.S. Prescriptions not guaranteed. Restrictions apply. Off-label products are not endorsed by the FDA.

Oral vs. Topical Finasteride

Some research directly compares oral finasteride (1 mg daily) with various concentrations of topical finasteride, aiming to match hair regrowth efficacy while minimizing systemic side effects. Let’s take a look at a couple of examples:

Study 1 – Piraccini et al., 2022 (Phase III RCT, 24 weeks)

• Compared topical finasteride (0.25% spray) to oral finasteride (1 mg/day) and placebo in men with AGA.^[2]Piraccini, B.M., Blume-Peytavi, U., Scarci, F., Jansat, J.M., Falques, M., Otero, R., Tamarit, M.L., Galvan, J., Tebbs, V., Massana, E., Topical Finasteride Study Group. Efficacy and safety of … Continue reading
• The increase in hair count on a defined scalp area was similar for topical and oral finasteride, both outperforming the placebo, suggesting comparable clinical benefit.
• Systemic finasteride (oral) reduced mean serum DHT by 55.6%,  whereas topical finasteride reduced it by 34.5%. Plasma finasteride exposure from topical application was over 100 times lower than from oral administration. 
• Both had similar low rates of mild side effects, but sexual side effects, but sexual side effects were more associated with oral treatment. 
• Caveats: The “target area” measured may not represent the full scalp effects; although systemic absorption, albeit at a much lower level with topical application, still occurred and varied by formulation. 

Study 2 – Bhura, 2013 (RCT, 8 months)

• Parallel-group comparison in male AGA, tracking hair density and systemic DHT.^[3]Bhura, M. (2013). Comparative Analysis of Topical and Oral Finasteride in Androgenetic Alopecia: Impact on Hair Growth, Systemic Absorption, and Adverse Effects. Indian Journal of Basic and Applied … Continue reading 
• Oral finasteride resulted in slightly superior increases in hair number and thickness, although the difference was not statistically significant.
• Oral finasteride significantly reduced systemic DHT and caused more sexual side effects; topical finasteride led to minimal serum DHT changes and almost no systemic side effects, with most reactions being local (e.g., irritation).
• Those worried about long-term systemic effects preferred topical use, despite slightly less pronounced gains.

Study 3 – Hajheydari, 2009 (RCT, 6 months)

• Compared a 1% topical gel + placebo tablet with oral finasteride 1 mg/day + placebo gel.^[4]Hajheydari, Z., Akbari, J., Saeedi, M., Shokoohi, L. (2009). Comparing the therapeutic effects of finasteride gel and tablet in treatment of the androgenetic alopecia. Indian Journal of Dermatology, … Continue reading 
• Both the gel and tablet produced statistically significant increases in total hair count and terminal hair count.
• There were no significant differences in hair thickness, hair count, or size of the bald area between the two groups. 

Mechanism of Action

Finasteride Pharmacodynamics

Finasteride is a competitive inhibitor of 5α-reductase, primarily targeting the type II isoenzyme at therapeutic doses, which predominates in the hair follicles and prostate. As mentioned above, this enzyme catalyzes the conversion of testosterone to DHT. 

At higher tissue concentrations, finasteride can also inhibit type I 5α-reductase, which is primarily found in the skin and sebaceous glands; however, its clinical significance for hair loss at standard doses is limited. By selectively inhibiting the type II enzyme, finasteride effectively lowers local and systemic DHT levels.^[5]Finn, D.A., Beadles-Bohling, A., Beckley, E.H., Ford, M.M., Gililland, K.R., Gorin-Meyer, R.E., Wiren, K.M. (2006). 12(1). 53-76. A New Look at the 5α-reductase Inhibitor Finasteride. CNS Drug … Continue reading 

What is Finasteride’s Effect on DHT Suppression?

Finasteride’s effect on DHT suppression is characterized by a logarithmic dose-response curve, meaning that even very low systemic levels can produce a marked reduction in both serum and scalp DHT. Most of the drug’s inhibitory action is achieved at low doses, with additional dosing yielding only marginal further effect.

As a result, even minimal “leakage” of topically applied finasteride into the bloodstream can decrease DHT levels elsewhere in the body.

Pharmacokinetic studies show that inhibition of type-II 5ɑ-reductase reaches saturation at typical clinical dosage, while type-1 enzyme inhibition requires much higher concentrations. This nonlinear pharmacodynamic profile explains both the strong efficacy and the wide safety margin of topical finasteride: a small amount achieves most of the desired effect, so careful formulation is crucial to maximize scalp delivery while minimizing unwanted systemic exposure.^[6]Suzuki, R., Satoh, H., Ohtani, H., Hori, S., Sawada, Y. (2010). Saturable Binding of Finasteride to Steroid 5ɑ-reductase as Determinant of Nonlinear Pharmacokinetics. Drug Metabolism and … Continue reading 

What the Science Says

Topical finasteride has been studied across a 200-fold concentration range, from 0.005% solutions to 1% gels. Collectively, these trials demonstrate meaningful reductions in shedding and measurable regrowth; however, systemic exposure increases with dose and vehicle potency.

Study	Concentration & Vehicle	Hair Growth-Outcomes	Systemic/Serum Findings
Mazzarella 1997, single-blind, 52 men/women, 16 months.	0.005% hydro-alcoholic solution	73% reported “high effectiveness”; wash-test hair counts improved; slowed shedding by month 6	No significant change in plasma DHT or testosterone; absorption was negligible.
Tanglertsampan 2012 RCT, 33 men, 24 weeks.	0.1% lotion + 3% minoxidil	The combination arm gained more hairs/cm2 and thicker shafts than minoxidil alone.	Local irritation mild; systemic parameters not monitored.
Datta 2021 double-blind trial, 35 participants completed, 6 months.	0.1% lotion +5% minoxidil vs oral 1 mg.	The topical combination was non-inferior to oral minoxidil for reducing the Hamilton-Norwood stage.	Sexual adverse events only occurred in the oral group; topical was well-tolerated.
Caserini 2016 OK study, 50 men, 1 week; Piraccini 2022 phase III, 323 completers, 24 weeks.	0.25% solution.	-70% scalp DHT after once-daily 1 mL; +20.2 hairs in 1 cm2 target area at 24 weeks – numerically equal to oral 1 mg.	100-200 μL doses reduced serum DHT by only 24-26%; 400 μL treatment reduced levels by 44-48%; Cmax was more than 100 times lower than oral.
Rossi 2020 retrospective, 69 women, 12-18 months.	0.5% lotion (postmenopausal women)	The Finasteride + minoxidil group scored higher on a 7-point global scale compared to the 17ɑ-estradiol + minoxidil group.	No androgenic side effects reported.
Hajheydari 2009 DB-RCT, 45 men, 6 months.	1% gel	Increases in total and terminal hair counts matched those of oral 1 mg; the bald area remained unchanged.	Serum DHT not assayed; clinical side-effects minimal.

Low-Dose Takeaways

Even a micro-dose of 0.005% twice daily (~0.1 mg/day) curbed shedding and improved density without measurable systemic suppression, making it an attractive option for highly risk-averse users.^[7]Mazzarella, F., Loconsole, F., Cammisa, A., Mastrolonardo, M., Vena, G.A. (1997). Topical finasteride in the treatment of androgenic alopecia. Preliminary evaluations after a 16-month therapy course. … Continue reading

Mid-Range (0.1-0.25%)

Adding 0.1% finasteride to minoxidil amplifies regrowth compared to minoxidil alone, while standalone 0.25% sprays deliver oral-level scalp DHT blockade, maintaining serum exposure roughly one-tenth that of tablets. Dose and volume are critical.^[8]Caserini, M., Radicioni, M., Leuratti, C., Terragni, E., Iorizzo, M., Palmieri, R. (2016). Effects of a novel finasteride 0.25% topical solution on scalp and serum dihydrotestosterone in healthy men … Continue reading

High-Dose (0.5-1%)

Topical finasteride options at 0.5% have been shown to extend benefits to female pattern hair loss with good tolerability.^[9]Rossi, A., Magri, F., D’Arino, A., Pigliacelli, F., Muscianese, M., Leoncini, P., Caro, G., Federico, A., Fortuna, M.C., Carlesimo, M. (2020). Efficacy of Topical Finasteride 0.5% vs 17ɑ-Estradiol … Continue reading

Why Formulation and Dose Matter

1. The vehicle drives absorption: according to the studies, hydro-alcoholic sprays penetrate faster than gels or liposomes, explaining divergent serum DHT curves at equal nominal strengths. 
2. Daily drug load, not percentage alone, predicts systemic spill over; 0.025% at 400 μL approaches the systemic impact of oral dosing, whereas 100 μL does not.
3. Combination therapy often allows for a lower finasteride concentration to achieve equal cosmetic benefits, thereby minimizing exposure.

Minimizing Systemic Absorption

While topical finasteride offers an option for minimizing systemic exposure, several key variables influence the amount that enters the bloodstream, and this can occur surprisingly quickly.

Key Factors Affecting Systemic Absorption

• Carrier Agent: The vehicle used to deliver finasteride dramatically alters absorption. Alcohol-based (ethosomal) carriers enhance drug penetration through the skin and into deeper layers like the dermis much more than conventional liposomes, which tend to remain more superficial. One study found that ethosomes resulted in approximately six times greater dermal accumulation than liposomes, highlighting the direct impact of carrier choice on systemic exposure.^[10]Rao, Y., Zheng, F., Zhang, X., Gao, J., Liang, W. (2008). In Vitro Percutaneous Permeation and Skin Accumulation of Finasteride Using Vesicular Ethosomal Carriers. AAPS PharmSciTech. 9(3). 860-865. … Continue reading
• Time on Scalp Before Washing: The longer finasteride remains on the scalp before washing, the greater the chance for absorption through the skin. Washing off too soon reduces drug uptake, but leaving it for extended periods increases both local efficacy and systemic exposure. Guidelines often recommend allowing at least 4-6 hours on the scalp, though this can vary by formulation. 
• Frequency of Use: If you can keep topical finasteride on your scalp for at least 10-12 hours, once-daily applications of low-dose topical finasteride might be beneficial. For those who can only tolerate finasteride for 4-6 hours, twice-daily applications may be better. You can read more about how often topical finasteride should be applied here.
• Individual Skin Permeability: Personal factors, including skin thickness, barrier integrity, genetics, and even scalp conditions, can strongly influence how much finasteride penetrates the scalp. Individuals with more permeable skin may absorb a greater amount of the drug systemically, increasing the risk of side effects.^[11]Brito, S., Baek, M., Bin, B-H. (2024). Skin Structure, Physiology, and Pathology in Topical and Transdermal Drug Delivery. Pharmaceutics. 16(11). 1403. Available at: … Continue reading 

How To Maximize Gains and Minimize Risk

To achieve the best results and reduce the likelihood of side effects, there are several strategies you can employ:

• Establish a Baseline with Serum DHT Testing

Before starting topical finasteride, get a baseline measurement of your serum DHT levels through a blood test. This serves as a reference to assess the extent to which systemic DHT is affected by your treatment. 

• Retest After 30 Days

After one month of consistent topical use, repeat the serum DHT test under the same conditions (preferably in the morning, fasted, and at a similar time of day). This helps you gauge systemic absorption and adjust your regimen if your serum DHT levels drop excessively. Hormone levels fluctuate based on daily rhythms, food intake, and stress, so always test under similar circumstances: morning, fasted, and ideally before applying the day’s finasteride.

• Avoid Confounding Supplements

Avoid supplements that may directly affect DHT, such as those that increase DHT (e.g., creatine) or quercetin (which may lower it). This ensures your test results and progress are a direct reflection of the topical finasteride.^[12]van der Merwe, J., Brooke, N.E., Myburgh, K.H. (2009). Three weeks of creatine monohydrate supplementation affects dihydrotestosterone to testosterone ratio in college-aged rugby players. Clinical … Continue reading,^[13]Ma, Z., Nguyen, T.H., Huynh, T.H., Do, P.T., Huynh, H. (2004). Reduction of rat prostate weight by combined quercetin-finasteride treatment is associated with cell cycle deregulation. Journal of … Continue reading 

• Be Patient – It Takes Time

Visible improvements often require 12-24 months. Don’t make hasty adjustments if you don’t see immediate changes; hair cycles are slow. 

• Track Your Progress Objectively

Use standardized, high-quality photo documentation, same angle, lighting, and distance each time, to objectively monitor changes in hair density and coverage.

Combination Therapies

Robust evidence supports the use of combination therapies for AGA, with multi-modal approaches consistently outperforming monotherapy in terms of efficacy and speed of regrowth.

Finasteride + Minoxidil: Studies show that pairing topical finasteride with 5% minoxidil yields superior hair density and patient satisfaction compared to either agent alone, particularly after 24 weeks of treatment.^[14]Apoorva, V.B., Vibhu, M., Singh, R.H., Smita, T. (2023). Comparative Efficacy of Topical Finasteride (0.25%) in Combination with Minoxidil (5%) Against 5% Minoxidil or 0.25% Finasteride Alone in Male … Continue reading,^[15]Rossi, A., Caro, G. (2023). Efficacy of the association of topical minoxidil and topical finasteride compared to their use in monotherapy in men with androgenetic alopecia: A prospective, randomized, … Continue reading,^[16]Abeck, F., Hansen, I., Kott, J., Schroder, F., Garrahy, E., Veneroso, J., Runger, A., Torster, L., Schneider, S.W., von Buren, J. (2024). Patient-reported outcomes of topical finasteride/minoxidil … Continue reading This combination is effective for both new users and those who have experienced shedding after discontinuing oral finasteride.

Finasteride + Microneedling: Adding microneedling to topical therapy can significantly enhance outcomes. Clinical trials demonstrated that combining microneedling with minoxidil and/or finasteride increased hair density and shaft diameter more than minoxidil alone, with effects noticeable within just 12 weeks.^[18]Chang, Y., Zhang, W., Zhou, J., Lv, L., He, Q., Chen, Y., Wang, P., Zhai, Q. (2025). Clinical efficacy of microneedle combined with 5% Minoxidil solution and finasteride in the treatment of … Continue reading,^[19]Adistri, K., Sirait, S.P., Rihatmadja, R., Legiawati, L., Indriatmi, W., Saldi, S.R.F. (2024). Effectiveness and safety of the combination therapy of micro-needling and minoxidil in androgenetic … Continue reading 

Triple Topical Therapy: Preliminary studies on formulations that combine finasteride, dutasteride, and minoxidil show promising results, with visible regrowth as early as three months in some cases.^[20]Rafi, A.W., Katz, R.M. (2011). Pilot Study of 15 Patients Receiving a New Treatment Regimen for Androgenic Alopecia: The Effects of Atopy on AGA. ISRN Dermatology. 241953. Available at: … Continue reading

So, combination therapy appears to be more effective than monotherapy. Therefore, leveraging two or more topical therapies or adding microneedling can support hair regrowth outcomes.

Who Should (or Shouldn’t) Use Topical Finasteride?

Good Candidates:

• Men diagnosed with AGA.
• Those who tolerate oral finasteride but seek to minimize systemic risks.

Not Ideal For: 

• People with hair loss from causes other than AGA (e.g., alopecia areata, telogen effluvium). 
• Those who have previously shown a poor response to finasteride.
• Anyone trying to conceive, or with infants, toddlers, or pregnant individuals in close contact.
• Users who are unable or unwilling to follow consistent application routines or medical monitoring. 

Final Verdict

Topical finasteride is a legitimate option for hair regrowth. When formulated and used properly, it can rival oral finasteride’s effectiveness with a lower risk of systemic side effects. Success hinges on the right delivery method, correct dilution, and consistent application. While not flawless, it excels as part of a comprehensive regimen, especially when paired with therapies like minoxidil or microneedling. 

For those hesitant about oral medication, topical finasteride offers a practical, lower-risk compromise, provided users carefully follow evidence-based protocols to optimize both safety and results. Used strategically, it is a potent addition to hair loss treatment plans.

Topical minoxidil is a first-line treatment for female pattern hair loss (FPHL) and other conditions such as telogen effluvium and traction alopecia. Many women of reproductive age use minoxidil and may wonder about its safety when trying to conceive or in early pregnancy.

While most reproductive safety discussions focus on oral or systemic medications, even topically applied drugs can raise questions about potential effects on fertility or early fetal development. Although systemic absorption from topical formulations is low, uncertainty persists regarding potential hormonal or embryonic effects.

This article examines available evidence to evaluate whether topical minoxidil poses any risk to female fertility or conception. By reviewing preclinical studies and clinical and pharmacological data, we aim to clarify whether there is any risk associated with topical minoxidil when trying to conceive.

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Topical Minoxidil: Mechanism and Pharmacology

Minoxidil may promote hair growth through several complementary mechanisms. After topical application, the drug is enzymatically converted by sulfotransferase (SULT1A1) into minoxidil sulfate, its active form. This metabolite enhances potassium channel activity within follicular cells, promoting cell proliferation and prolonging the anagen (growth) phase of the hair cycle. Additionally, minoxidil increases vascularity around the follicle by stimulating vascular endothelial growth factor (VEGF), improving oxygen and nutrient delivery to support stronger, thicker hair growth.^[1]Suchonwanit, P., Thammarucha, S., & Leerunyakul, K. (2019). Minoxidil and its use in hair disorders: a review. Drug Design, Development and Therapy. 13. 2777-2786. Available at: … Continue reading

There are important pharmacological distinctions between topical and oral formulations. Topical minoxidil acts locally on the scalp with minimal systemic absorption, which significantly reduces the risk of adverse effects. In contrast, oral minoxidil can cause systemic side effects, such as fluid retention, weight gain, increased blood pressure (hypertension), and other cardiovascular changes.^[2]StatPearls Editorial Team. (no date). Minoxidil. In: StatPearls [Internet]. StatPearls Publishing. Available at: https://www.ncbi.nlm.nih.gov/books/NBK482378/ (Accessed: October 2025)

Female Fertility: What Matters When Trying to Conceive?

Female fertility relies on coordinated hormonal cycles, healthy egg development, and a receptive uterine environment. Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) regulate ovulation, while estrogen and progesterone prepare the uterus for implantation and support early pregnancy.^[3]Thiyagarajan, D. K., Basit, H., & Jeanmonod, R. (2024 Jan 1). Physiology, menstrual cycle. In: StatPearls [Internet]. StatPearls Publishing. Available at: … Continue reading In addition to hormonal balance, healthy reproductive anatomy is important: clear fallopian tubes, a healthy uterus, and a cervix free of significant abnormalities are required for fertilization and embryo implantation.^[4]Mayo Clinic Staff. (no date). Female infertility – Symptoms & causes. Available at: https://www.mayoclinic.org/diseases-conditions/female-infertility/symptoms-causes/syc-20354308/ (Accessed: … Continue reading

Of course, women, or individuals who are female at birth, looking to conceive also need to consider the impact of medications following conception. The safe use of medications is essential to support maternal health and healthy fetal development while minimizing risks of complications and birth defects (teratogenic effects).

Systemic medications can interfere with fertility and pregnancy by disrupting hormonal balance or exerting teratogenic effects. For example, antiandrogens such as spironolactone, cyproterone acetate, and finasteride, sometimes prescribed for female hair loss, are contraindicated when trying to conceive due to their potential impact on fetal development.^[5]BinJadeed, H. F., & Alajlan, A. (2021). Pregnancy and neonatal outcome with maternal exposure to finasteride: a case series. Journal of Dermatology and Dermatologic Surgery. 25(2). 84-86. … Continue reading,^[6]Wu, M., Yu, Q., & Li, Q. (2016). Differences in reproductive toxicology between alopecia drugs: an analysis on adverse events among female and male cases. Oncotarget. 7(50). 82074-82084. … Continue reading Animal models suggest these agents interfere with androgen signaling, which is essential for normal sexual differentiation, particularly in male fetuses.^[7]Conley, J. M., Lambright, C. S., Evans, N., Cardon, M., Furr, J., Wilson, V. S., & Gray Jr, L. E. (2018). Mixed “antiandrogenic” chemicals at low individual doses produce reproductive tract … Continue reading In contrast, nutritional supplements like iron, vitamin D, and biotin are generally safe and can support overall reproductive health.

Systemic Absorption of Topical Minoxidil: How Much Gets In?

Topical minoxidil is formulated to act locally on the scalp, with only a small proportion entering systemic circulation – typically around 1–2%.^[8]Suchonwanit, P., Thammarucha, S., & Leerunyakul, K. (2019). Minoxidil and its use in hair disorders: a review. Drug Design, Development and Therapy. 13. 2777-2786. Available at: … Continue reading Pharmacokinetic studies show that this absorption rate can vary depending on several factors, including formulation strength (2% vs. 5%), frequency of application, and the integrity of the scalp barrier. Plasma minoxidil levels in individuals using topical formulations generally remain well below those associated with systemic pharmacologic or reproductive effects observed in animal studies.^[9]Singh, S., Patil, A., Kianfar, N., Waśkiel-Burnat, A., Rudnicka, L., Sinclair, R., & Goldust, M. (2022). Does topical minoxidil at concentrations higher than 5% provide additional clinical … Continue reading,^[10]Hsu, C. L., Liu, J. S., Lin, A. C., Yang, C. H., Chung, W. H., & Wu, W. G. (2014). Minoxidil may suppress androgen receptor‐related functions. Oncotarget. 5(8). 2187-2197. Available at: … Continue reading

By contrast, oral minoxidil is almost completely absorbed, leading to significantly higher plasma concentrations and systemic exposure. This explains why oral therapy, though often more potent, also carries a greater risk of systemic side effects, including edema, tachycardia, and generalized hypertrichosis.^[11]Randolph, M., & Tosti, A. (2021). Oral minoxidil treatment for hair loss: a review of efficacy and safety. Journal of the American Academy of Dermatology. 84(3). 737-746. Available at: … Continue reading

Does Topical Minoxidil Affect Female Fertility, Conception, or Pregnancy?

When considering the impact of medications on women’s fertility and ability to conceive, it is also essential to review the evidence regarding potential effects during pregnancy, as treatments will inevitably continue to be taken into early pregnancy, and systemic effects may be long-lasting. Here, we review preclinical and clinical evidence on whether topical minoxidil affects female fertility and pregnancy.

Preclinical Evidence

Minoxidil is classified as a non-hormonal treatment, suggesting it is unlikely to impact hormonal cycles that impact fertility. However, due to the relationship between hair growth and hormonal pathways, some preclinical research has focused on how minoxidil affects androgen pathways.

One cell-based study suggests that minoxidil can directly interact with and weaken androgen receptor signaling. However, this study used higher concentrations of minoxidil than would be used in hair loss treatment, and for practical purposes, topical minoxidil remains classified as a non-hormonal treatment.^[12]Hsu, C. L., Liu, J. S., Lin, A. C., Yang, C. H., Chung, W. H., & Wu, W. G. (2014). Minoxidil may suppress androgen receptor‐related functions. Oncotarget. 5(8). 2187-2197. Available at: … Continue reading

However, in an animal model using golden Syrian hamsters, 5% topical minoxidil did not prevent the androgen-dependent growth of pigmented spots, suggesting that minoxidil does not have any effect on androgen response.^[13]Nuck, B. A., Fogelson, S. L., & Lucky, A. W. (1987). Topical minoxidil does not act as an antiandrogen in the flank organ of the golden Syrian hamster. Archives of Dermatology. 123(1). 59-61. … Continue reading 

There is a significant lack of research using preclinical animal models investigating the impact of topical minoxidil on female fertility and during pregnancy. However, one small-scale study did examine the effect of 5% topical minoxidil on embryonic mortality in rats. They found no impact of daily minoxidil application over the course of 20 days of pregnancy compared to the control group. However, the sample size was relatively small (20 rats in total), and no molecular or cellular analysis was performed to look for potential mechanisms that could cause embryonic lethality.^[14]Turkina, V. A., Chemodurova, N. Y., Pryzyglei, H. V., & Kuzminov, Y. B. (2021). Potential embryotoxic effect study of minoxidil-containing lotion in experiment with female rats. Світ … Continue reading

Clinical Evidence

Unfortunately, a lack of research into the impact of medications on women and fetuses during pregnancy is a systemic issue within medicine. Pregnant women are generally excluded from clinical trials due to safety concerns, as well as the confounding impact of widespread hormonal changes associated with pregnancy.^[15]Stock, S. J., & Norman, J. E. (2019). Medicines in pregnancy. F1000Research. 8(F1000Faculty Rev):911. Available at: https://doi.org/10.12688/f1000research.17535.1 These issues extend to women trying to conceive, and most clinical trials have explicit protocols that remove individuals from clinical trials after they become pregnant.^[16]Phelan, A. L., Kunselman, A. R., Chuang, C. H., Raja-Khan, N. T., & Legro, R. S. (2016). Exclusion of women of childbearing potential in clinical trials of type 2 diabetes medications: a review … Continue reading

The safety of medications for pregnant women and their children is typically established after drugs have come to market, through observational studies and pharmacovigilance, which looks for cases where problems have arisen. While such processes are good at spotting signals of high risk, these forms of evidence are less powerful than clinical trials and cannot detect less impactful effects.

As such, determining the safety of drugs for pregnant women is often done using scarce information. As a result, many medications are contraindicated (their use is advised against) for pregnant women due to a lack of evidence, not because of evidence.^[17]Thomas, S. H., & Yates, L. M. (2012). Prescribing without evidence – pregnancy. British Journal of Clinical Pharmacology. 74(4). 691-697. Available at: … Continue reading  

Multiple reviews of the safety of dermatological treatments in pregnant women advise against the use of monoxidil.^[18]Koh, Y. P., Tian, E. A., & Oon, H. H. (2019). New changes in pregnancy and lactation labelling: Review of dermatologic drugs. International Journal of Women’s Dermatology. 5(4). 216-226. … Continue reading,^[19]Truong, T. M., Yaghi, M., & Murase, J. (2023). Dermatologic Drug Safety in Pregnancy. Journal of Dermatology for Physician Assistants. 17(3). 1-12. Available at: … Continue reading,^[20]Suchonwanit, P., Thammarucha, S., & Leerunyakul, K. (2019). Minoxidil and its use in hair disorders: a review. Drug Design, Development and Therapy. 13. 2777–2786. Available at: … Continue reading However, this advice appears to be based on two case studies where topical minoxidil was theorized as the cause of the birth defects. Case studies present a single individual (or group of individuals) where an event or phenomenon has occurred. They are a weak form of evidence and are typically used as the basis for larger studies. 

In one of these case studies, the pregnancy of a 28-year-old woman who was applying topical minoxidil was terminated due to the presence of fetal malformation. Topical minoxidil was suggested as a possible cause of teratogenesis.^[21]Smorlesi, C., Caldarella, A., Caramelli, L., Di Lollo, S., & Moroni, F. (2003). Topically applied minoxidil may cause fetal malformation: a case report. Birth Defects Research Part A: Clinical … Continue reading The other study noted a case of a rare condition called caudal regression syndrome in a fetus where the mother had been using topical minoxidil, though other causes were also proposed.^[22]Rojansky, N., Fasouliotis, S. J., Ariel, I., & Nadjari, M. (2002). Extreme caudal agenesis. Possible drug-related etiology?. Journal of the American Academy of Dermatology. 47(3). 241-245. … Continue reading These cases were published in 2002 and 2003, and both advised that further studies were warranted.

In a more systematic approach, one study analysed FDA Adverse Event Reporting System (FAERS) data, which collects evidence of adverse effects related to medications.^[23]Wu, M., Yu, Q., & Li, Q. (2016). Differences in reproductive toxicology between alopecia drugs: an analysis on adverse events among female and male cases. Oncotarget. 7(50). 82074-82084. … Continue reading The study used data collected between 2004 and 2014. Over the ten years analyzed, 2 cases of induced abortion and 2 cases of spontaneous abortion were reported in women using minoxidil. This represents around 2% of cases reported. For comparison, induced abortion represented around 18% of reported adverse effects related to finasteride, for which it was the most commonly reported issue. No cases related to sexual dysfunction or loss of libido were reported.

It is due to the lack of evidence and the potential issues that these case studies raise that minoxidil is typically contraindicated for women who are trying to conceive or are pregnant. There is no evidence to suggest that minoxidil has any impact on female fertility. Larger observational and controlled studies would be required to make evidence-based conclusions regarding the safety of minoxidil for women trying to conceive.

Summary Consensus

There is no direct evidence linking topical minoxidil to reduced fertility. The use of topical minoxidil is advised against for women trying to conceive due to a small number of reported cases where topical minoxidil was associated with fetal abnormalities. 

Counseling and Clinical Recommendations

The Food and Drug Administration (FDA) classifies topical minoxidil as a pregnancy category C drug. This means studies have shown a risk to the fetus, but there are no adequate, controlled studies in pregnant women. Such drugs are generally only prescribed if there is a significant benefit to the mother that outweighs potential risks. As such, a review published by the American Academy of Dermatology in 2025 advises against using minoxidil while pregnant.^[25]Olsen, E. A., Sinclair, R., Hordinsky, M., Mesinkovska, N. A., Sadick, N., Shapiro, J., & Bergfeld, W. (2025). Summation and recommendations for the safe and effective use of topical and oral … Continue reading In the UK, the National Institute for Health and Care Excellence (NICE) also advises against the use of topical minoxidil when pregnant or breastfeeding.^[26]National Institute for Health and Care Excellence. (no date). Female-pattern hair loss (female androgenetic alopecia) — Prescribing information: Topical minoxidil. Available at: … Continue reading

Does topical minoxidil cause infertility?

There is no evidence to suggest that topical minoxidil can impact fertility in women. There are a very limited number of cases reported where minoxidil has been associated with impotence in men.^[27]Rietschel, R. L., & Duncan, S. H. (1987). Safety and efficacy of topical minoxidil in the management of androgenetic alopecia. Journal of the American Academy of Dermatology. 16(3). 677-685. … Continue reading

Does minoxidil interfere with female hormones or ovulation?

There is limited research into the effect of minoxidil on female hormones or ovulation. However, minoxidil is not a hormonal drug, and there is limited evidence to suggest that it interferes significantly with hormones at levels associated with topical treatment.

Should women stop minoxidil months before trying to conceive?

While there is no evidence that minoxidil can impact women’s ability to conceive, it is not advised to use the treatment while pregnant. Therefore, it is recommended to stop using minoxidil while trying to conceive.^[28]Olsen, E. A., Sinclair, R., Hordinsky, M., Mesinkovska, N. A., Sadick, N., Shapiro, J., & Bergfeld, W. (2025). Summation and recommendations for the safe and effective use of topical and oral … Continue reading

Can minoxidil exposure cause miscarriage or birth defects?

There are limited case reports that associate topical minoxidil with birth defects and fetal malformation, leading to termination. These findings have not been expanded on by larger trials or observational studies.^[29]Smorlesi, C., Caldarella, A., Caramelli, L., Di Lollo, S., & Moroni, F. (2003). Topically applied minoxidil may cause fetal malformation: a case report. Birth Defects Research Part A: Clinical … Continue reading,^[30]Rojansky, N., Fasouliotis, S. J., Ariel, I., & Nadjari, M. (2002). Extreme caudal agenesis. Possible drug-related etiology?. Journal of the American Academy of Dermatology. 47(3). 241-245. … Continue reading

Do all hair loss drugs have the same reproductive risks?

Different hair loss treatments have fundamentally different mechanisms. Finasteride and dutasteride are hormonally active and may impact male fertility and fetal development.^[31]BinJadeed, H. F., & Alajlan, A. (2021). Pregnancy and neonatal outcome with maternal exposure to finasteride: a case series. Journal of Dermatology and Dermatologic Surgery. 25(2). 84-86. … Continue reading,^[32]Wu, M., Yu, Q., & Li, Q. (2016). Differences in reproductive toxicology between alopecia drugs: an analysis on adverse events among female and male cases. Oncotarget. 7(50). 82074-82084. … Continue reading Risks associated with minoxidil are significantly less well established, and adverse reproductive events have been shown to be significantly lower than finasteride.^[33]Wu, M., Yu, Q., & Li, Q. (2016). Differences in reproductive toxicology between alopecia drugs: an analysis on adverse events among female and male cases. Oncotarget. 7(50). 82074-82084. … Continue reading

Latest Research and Knowledge Gaps

There is a significant gap in our knowledge of whether minoxidil affects pregnancy and the mechanisms by which it might do so. Data from preclinical models has focused on hair cycle dynamics rather than reproductive parameters, with only limited research on its impact on androgenic hormonal pathways.

Both of the case studies that associated topical minoxidil with adverse pregnancy outcomes are over 20 years old, with no follow-up studies to better understand these reports. Clinical trials or observational studies would be necessary to make evidence-based assessments on the safety of minoxidil during pregnancy and its impact on female fertility.

Final Thoughts

Current evidence does not show that topical minoxidil impairs fertility or conception. However, because pregnancy safety data remain incomplete, discontinuation is recommended when planning conception – a precautionary measure rather than a proven necessity.

For women experiencing distressing hair loss, treatment decisions should balance cosmetic benefit with potential but unproven reproductive risk, ideally in consultation with a dermatologist or reproductive health specialist.