How to Reduce the Risk of Finasteride Side Effects

Finasteride Side Effects

Finasteride is the most powerful, well-studied, FDA-approved drug for androgenic alopecia (AGA). It stops AGA progression in 80-90% of men and, on average, leads to a 10% increase in hair count over two years. For men wanting a hands-off approach to hair maintenance finasteride is often an excellent option.

That said, finasteride isn’t for everyone. While its risk of side effects are often overstated online, the drug appears to reduce libido in a certain percentage of men and may induce gynecomastia. The drug 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. 

The true incidence and magnitude of these reports are hard to discern. Depending on the study we cite and the questionnaire design, these effects can range from 1% to 40%. Whether or not one should worry about finasteride side effects may depend on their current hormonal profile and mental health. Keep reading to learn more.


Gynecomastia is the growth of male breast tissue. It results from elevated hormones such as prolactin and estrogen. While gynecomastia is estimated to only affect between 0.25-1.00% of people on 5-alpha reductase inhibitors (such as finasteride), those who start the drug with already elevated levels of prolactin and estrogen are likely at a higher risk of its development. 

Drugs like finasteride can raise blood levels of both testosterone and estrogen by 10-30%, depending on the dose. So, for those starting the drug with borderline-high estrogen, the additional lift in estrogen levels may put someone at greater risk of gynecomastia.

Sexual Side Effects

Because it lowers DHT levels (a hormone that helps maintain male sex characteristics), some studies have shown that a percentage of finasteride users report sexual side effects ranging from decreased sex drive to reduced semen volume to erectile dysfunction. Studies vary widely, but incidents could be as low as 1-2% of users.

Female users should be aware that Finasteride can potentially mutate and/or inhibit the development of male fetus genitalia.[1]dailymed.nlm.nih.gov/dailymed/lookup.cfm As such, pregnant women are neither prescribed finasteride nor advised to even handle the medication. 

Cognitive Side Effects

On hair loss forums, some men taking finasteride have complained of changes to cognition, specifically, a feeling of brain fog since starting therapy. To date, this hasn’t been reported to significant degrees in clinical studies. This may be because even if the effects do exist, it’s likely a subtle, gradual side effect that many may not attribute to the drug. 

Animal models have demonstrated that finasteride can indeed change brain chemistry, especially after transitioning off of the drug. But it’s important to note that animals in those studies take dosages of finasteride thousands of times greater than what is prescribed to humans.

In any case, it’s not unreasonable that those with depression, anxiety, and/or bipolar disorder should proceed with caution and speak with their doctor to closely monitor the effects of finasteride use.

How To Reduce Side Effects Of Finasteride

Regardless of the specific side effect that’s being targeted to reduce, the strategies are all similar: find ways to (1) reduce daily drug exposure, (2) localize the drug’s effects to the scalp, and (3) do lab tests to determine personal risk for certain side effects like gynecomastia. These strategies are outlined in detail below:

Limit Daily Drug Exposure

As a hair loss drug, finasteride is typically prescribed orally at 1mg daily. Having said that, there’s evidence that 0.2mg daily is nearly just as effective at improving hair counts while simultaneously reducing total drug exposure by 80%. For many people, this coincides with a reduction in perceived side effects.

If side effects, or anticipatory anxiety, are a concern, try lowering the dose of the drug. Unfortunately, finasteride is a hair loss drug that must be continued indefinitely for its effectiveness to remain. When finasteride treatment is stopped, men typically lose what hair regrowth they gained within 3-12 months.

If Finasteride’s side effects don’t go away with reduced usage, rest assured that most users report these side effects do go away with discontinued drug use, for some within 2-3 weeks.

Localize Finasteride’s Effects to the Scalp

There are two primary ways to localize finasteride’s effects to the scalp. These methods minimize the amount of the drug that circulates throughout the bloodstream, thus minimizing the side effects of finasteride. Both entail switching from an oral to topical formula.

  • Try a topical formulation

Studies show that – when formulated properly – topical finasteride may reduce the risk of side effects by 30-90%. One 16-month study on 0.005% topical finasteride demonstrated significant hair improvements, no drug-associated side effects, and no impact on blood hormonal levels. This suggests there was no absorption of the drug beyond the scalp. 

Similarly, another research group reported that 0.15% topical finasteride formulated with liposomes (a fat-based carrier agent) resulted in great hair growth, minimal systemic absorption, and no sexual side effects.

  • Try intradermal delivery methods

Also known as mesotherapy, intradermal delivery methods inject finasteride into the scalp. Evidence suggests that scalp injections once every 1-3 months do not appreciably alter serum hormones, nor do they result in any reported cognitive or sexual side effects. They still lead to statistically significant hair improvements. 

Injections are more commonly done with dutasteride than finasteride, as dutasteride has a longer half-life and can confer longer-lasting scalp tissue DHT reductions with far fewer yearly mesotherapy sessions.

Determine Your Risk for Finasteride Side Effects

Determining personal risk ahead of time, and getting a baseline measure of hormonal health, can help people decide if finasteride is right for them. It can also help people keep track of how the drug is influencing their serum hormones.

Testing for Gynecomastia Risk

For peace of mind, blood tests for prolactin and estrogen can be ordered prior to starting finasteride. Retest a few months after use has begun. If hormonal levels are within range, the risk of gynecomastia is likely much lower. Anyone can do this with the help of their primary care physician. Or, those based in the U.S. (or any other country that offers direct-to-consumer lab testing) may be able to order tests through the links below.

For more information, see these resources:

Testing for Sexual Side Effect Risk

Those worried about the sexual side effects of finasteride, and also using a topical formulation or intradermal injections, can test their own blood levels of DHT (the hormone lowered by finasteride). This grants the ultimate peace of mind by allowing for quantification of the exact changes to serum DHT levels before and during treatment. 

Changes to serum DHT levels can help people understand just how much topical finasteride (if any) is going systemic. In general, DHT fluctuations smaller than 20% are considered biologically insignificant. Directions for how to do this can be found inside our comprehensive finasteride guides, available for members[4]https://perfecthairhealth.com/join-now/.

So, consider these options (and the data) before giving up entirely on finasteride. There are many ways to leverage its power, mitigate its risks, and perhaps take hair regrowth to a new level.

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