Read time: 15 minutes
Why This Article?
I was diagnosed with male pattern hair loss before graduating high school. The prospect of being bald by my mid-to-late twenties terrified me. I spent the better part of a decade researching ways to reverse the condition. I bought every hair care product I could find. I used Rogaine for six years. I even tried laser therapy, albeit very briefly.
Reflecting back, I’m thankful for the diagnosis. It catalyzed a desire to better understand my body, my health, and why my hair was falling out.
This article discusses the reasons why hair loss drugs rarely (if ever) result in 100% reversals of pattern hair loss. And of the drugs that are somewhat effective, these might not be working via their intended mechanisms. For some people taking prescription hair loss drugs, the treatment can be worse than the disease.
DHT – The Cause Of Hair Loss, Or A Misunderstood Symptom?
If you’ve ever looked into the causes of hair loss, you’ve probably heard of dihydrotestosterone, or DHT. DHT is a hormone that comes from testosterone. DHT levels are higher in people with thinning hair.
Because of this connection, most hair loss surgeons say that DHT is the root cause of hair loss. Their explanation is as follows: for reasons not fully understood, higher amounts of DHT begin to bind to scalp tissues. The scalp’s hair follicles become sensitive to the elevated DHT and shrink over a series of hair cycles. This process eventually leads to thinner, wispier hair, until the hair disappears and follicles become dormant. Here’s a picture:
What’s wrong with that explanation? It’s only partially true. Yes, DHT is implicated in hair loss. But it’s just one of many symptoms observed in those with thinning hair. There are a variety of other factors that are largely ignored by hair loss surgeons. Some of these factors are:
- Calcification of the scalp sutures
- Calcification of blood vessels leading to the hair follicles
- Fibrosis of the scalp skin and hair follicles
- Collagen remodeling of balding scalp tissue
Interestingly, elevated DHT isn’t just observed in balding scalps… It’s also observed in inflamed body tissues. There’s also evidence that DHT actually helps regulate inflammation, and that in some tissues, DHT is anti-inflammatory.
Now let’s take another look at that list of conditions. Of the above factors, there are two major threads: fibrosis and calcification. What do both have in common?
If chronic inflammation leads to calcification and fibrosis, and elevated DHT is a response to inflammation, then DHT probably isn’t the root cause of hair loss. DHT is probably just a symptom of a chronically inflamed scalp.
Unfortunately, nearly all hair growth drugs are designed to block your body’s DHT production. But these drugs don’t address the inflammation. As a result, they aren’t very effective. They’re also dangerous, since DHT production is critical to sexual health, and inhibiting it can lead to erectile dysfunction and even impotence.
What Are Hair Growth Products, And How Do They Work?
The Big Three
Of the few FDA-approved hair growth drugs, these are the most popular:
- Finasteride (branded as Propecia)
- Dutasteride (branded as Avodart)
- Minoxidil (branded as Rogaine)
Finasteride Prevents DHT Conversion
How does Finasteride work? Finasteride prevents testosterone from converting to DHT, so that less DHT collects on your scalp. Testosterone is converted to DHT by the enzyme 5-alpha reductase. Finasteride is a 5-alpha reductase inhibitor (or blocker). The conventional rationale is as-follows: by inhibiting testosterone’s conversion to DHT, less DHT gets to your scalp, so you lose hair less quickly. If enough DHT is blocked, you might even halt hair loss or experience minor regrowth.
Dutasteride Does The Same Thing
Dutasteride is very similar to Finasteride, but was never intended to treat male pattern hair loss. It was originally developed to reduce the size of enlarged prostate glands by acting as a 5-alpha reductase inhibitor. After realizing that the drug helped reduce the conversion of testosterone to DHT and in some cases reduce hair loss, it was later rebranded as a hair loss treatment.
Minoxidil Provides Blood Flow To Scalp
Minoxidil provides blood flow to the follicles. When applied twice daily, it can help reduce and sometimes stop hair loss by allowing a little more circulation to get to your hair. It doesn’t prevent the DHT build-up in the scalp. The mechanisms by which Minoxidil halts hair loss still aren’t fully understood.
What’s The Problem With Finasteride Or Dutasteride?
Finasteride & Dutasteride Can Ruin Your Sex Life Forever
The enzyme 5-alpha reductase plays a number of hormonal roles in the body, many of which aren’t yet fully understood. Finasteride & Dutasteride inhibit this enzyme, which yields unintended consequences. For example – in some men, taking Finasteride for a mere few weeks resulted in unresolved erectile dysfunction, even after stopping the prescription.
Fasteride & Dutasteride Use May Result In Prostate Cancer
In 2011, Finasteride and Dutasteride (eg, anything branded as Propecia, Proscar, Avodart, or Jalyn) were forced by the FDA to amend their warning labels after research suggested that prolonged use increased the risk of high-grade prostate cancer. Think about that. These drugs are intended to reduce enlarged prostate glands, but might give you prostate cancer in the process.
That doesn’t sound like a fair trade-off, especially when you’re the one paying for the prescription.
Finasteride & Dutasteride Reduce Your Sperm Count
In 2007, scientists found that Finasteride and Dutasteride reduced total sperm count by ~30% after 6 months of use. Sperm volume, concentration, and motility were also reduced. Because of this (and the other long-lasting hormonal changes these drugs induce), you can’t donate blood until you’ve stopped using Finasteride for 1 month and Dutasteride for 6 months.
Pregnant Women Aren’t Allowed To Even Touch Finasteride & Dutasteride
Why can’t women use either of these 5-alpha inhibiting drugs? Because Finasteride and Dutasteride can potentially mutate and inhibit the development of male fetus genitalia. Women are even advised to avoid touching the drugs’ capsules if they are pregnant.
What About Minoxidil?
Rogaine’s Ingredients Are Banned In Other Countries
If you’re unconcerned about using Minoxidil, it’s worth mentioning that some of the ingredients in Rogaine Foam are banned outside the US because they are considered carcinogenic and tumor-promoting. This is a product you put on your scalp, everyday, twice a day. That’s pretty close to a few important things – your brain and your eyes to name a few. With each application, you roll the dice for cell mutation. It seems like quite a risk, especially when its efficacy is more limited to arresting hair loss, not necessarily reversing it.
Rogaine Kills Cats (Don’t Get Any Ideas)
For reasons not entirely understood, Minoxidil is also highly toxic to cats – so toxic that some have died just through unassuming skin exposure to the drug. Regardless of how you feel about cats, how can this be good for humans? Rogaine is to cats as insecticide is to insects, and cats are much closer in size to humans than insects. Are you sure you want this on your scalp everyday? (Update: please see the comments section for further explanation on this analogy.)
Minoxidil’s Ability To Stop Hair Loss Isn’t Even Understood
Similar to Finasteride, Minoxidil’s ability to slow hair loss also isn’t fully understood. I’m a firm believer that you should never put something unnatural into your body, especially if you don’t understand how it works. While the same level of research isn’t there, who is to say that Minoxidil isn’t capable of the similar unintended consequences as Finasteride or Dutasteride?
Then Why Do Some People See Regrowth With Finasteride, Dutasteride, And Minoxidil?
While Finasteride and Dustasteride are designed to inhibit DHT conversion, that’s probably not the mechanism by which these drugs help to achieve minor hair regrowth.
Aside from reducing DHT, Finasteride also downregulates MMP2 and MMP9. MMP2 and MMP9 are two protein coding genes that influence collagen modeling and remodeling. Collagen remodeling is on our list of conditions associated with balding scalps. There’s a good chance that much of Finasteride’s regrowth success is contingent on the effects it exerts on collagen.
As far as Minoxidil – we know that Minoxidil increases blood flow to the scalp. But how? Aside from opening potassium ion channels, new research indicates Minoxidil also increases Prostaglandin E2 (PGE2) at the sites where it’s applied. Increased PGE2 is associated with vasodilation, muscle relaxation, inflammation resolution, and even the anagen (growth) stage of the hair cycle. We know that calcification of the scalp sutures and blood vessels supporting hair follicles can significantly restrict blood flow at balding sites. If Minoxidil increases blood flow, it probably helps counteract (to a degree) calcification or fibrosis, and temporarily maintain hair – at least for however long it’s used.
In either case, the reason why we don’t see 100% recoveries from either drug is probably because they don’t target the causes of hair loss that are furthest upstream – inflammation – nor do they resolve the chronic, progressive conditions that chronically elevated DHT (in combination with other factors) can cause – calcification and fibrosis.
Without Addressing Inflammation, Fibrosis, And Calcification, These Products Will Never Be 100% Effective
Minoxidil may stimulate blood flow to the scalp, and Finasteride may help prevent the conversion of testosterone to DHT, but these are just band-aids to larger underlying causes of hair loss. They never actually strike the core of the issue, and so they’ll never really result in permanent reversals.
What’s worse, success rates for hair transplants aren’t very high because your healthy hairs are often transferred into calcified areas. It’s only a matter of time before they die out, too. That’s why you’re asked to use Rogaine or Propecia after a hair transplant – since you need all the help you can get.
Inflammation is further upstream to hair loss than DHT. Calcification and fibrosis are chronic, progressive conditions downstream to DHT, but by taking away DHT, you don’t take away the already-existing calcification and fibrosis. It’s my belief that this is why hair loss drugs targeting DHT are so ineffective and limited to slowing, not reversing, the condition. If you want to reverse hair loss, you should target calcification and fibrosis.
Rob English is a researcher, medical editor, and the founder of perfecthairhealth.com. He acts as a peer reviewer for scholarly journals and has published two peer-reviewed papers on androgenic alopecia. He writes regularly about the science behind hair loss (and hair growth). Feel free to browse his long-form articles and publications throughout this site.