Finasteride for Transgender Folks: For Hair Loss and Gender-Affirming Care

While finasteride is typically celebrated for its ability to treat hair loss and benign prostatic hyperplasia, the medication is also sometimes used by transgender individuals as part of gender-affirming therapy (GAHT).

Finasteride for trans women and trans men can serve different purposes and have different effects. Finasteride alters hormone levels. Hormones, of course, affect everything from hair loss to body hair to breast development.

Here, we’ll cover the basics of finasteride, plus the potential role of finasteride for transgender health and gender-affirming care.

Finasteride is part of a class of medications called 5 alpha-reductase inhibitors (5ARIs). It’s a mouthful, but 5 alpha-reductase is an enzyme that converts testosterone into another male sex hormone, dihydrotestosterone (DHT). 5ARIs block (or inhibit) this conversion.

But what does this have to do with hair loss? Well, it turns out quite a lot. DHT plays an important role in early development (it helps form male sex organs during fetal development and later helps to deepen the voice). But it also binds to androgen receptors in the hair follicles, which can cause hair loss. 

Finasteride stops DHT from getting into the hair follicle in the first place.

Oral finasteride (the active ingredient in Propecia®)is one of two medications approved by the U.S. Food & Drug Administration (FDA) for the treatment of male pattern baldness (also called androgenetic alopecia (AGA). Topical finasteride is used off-label for hair loss but hasn’t yet received FDA approval. 

Transgender men can take finasteride, but they should do so under the guidance of a healthcare provider to ensure it aligns with their overall treatment goals and health needs.

Sometimes, finasteride is prescribed to trans men to treat hair loss (just as it is to cis men). As masculinizing therapy is associated with an increased risk of developing male pattern baldness.  

But finasteride isn’t typically prescribed to trans men as part of hormone replacement therapy, as the drug may, in some cases, actually have feminizing side effects.

According to a survey-based study conducted via social media, 43 percent of surveyed trans men reported hair loss or thinning — hair loss was more common among trans men on masculinizing hormone therapy (45 percent) than those who were not on hormone therapy (17 percent). According to the research, “participants also reported significant worsening of hair loss after starting testosterone therapy.” 

Further, research shows that the hair growth cycle can be interrupted in people receiving masculinizing hormone therapy (MHT), with the highest instance of baldness occuring in the fourth year of MHT. 

Finasteride can be very effective in treating hair loss in trans men. In one small study, 10 transgender men were given 1 mg of finasteride (the standard finasteride dose) for somewhere between four and six months. All the patients improved one grade on the Norwood–Hamilton scale, a classification system used to measure the severity of male pattern baldness.

While finasteride is very effective for treating hair loss, there are a few things trans men thinking of taking finasteride should consider.

Finasteride’s Interaction with Testosterone Therapy

Trans men often take testosterone as part of their hormone therapy, which helps increase muscle mass, change fat distribution, and improve body hair growth.

Finasteride Side Effects

As with any medication, finasteride can have side effects, including sexual side effects like reduced libido and erectile dysfunction. 

That said, less than 2 percent of men experience sexual side effects, according to prescribing information from the FDA.

However, in rare cases, finasteride can cause gynecomastia or male breast development, which we’ll cover in our FAQ section.

Medical Supervision

Regular monitoring by a healthcare provider is important to track finasteride's effects and make any necessary adjustments to the treatment plan. It is also worth noting that finasteride is not FDA-approved for women due to its potential to cause birth defects, so if a trans man wishes to get pregnant, it’s not a good option.

Transgender women may take finasteride to manage hair loss, reduce unwanted body and facial hair, and achieve other feminizing effects by lowering DHT levels. 

Finasteride is sometimes used to treat hirsutism, a condition that causes unwanted male-pattern hair growth on the face, chest, or back in women. The medication may be offered to trans women to help decrease facial and body hair, though studies show it is only “modestly effective” in reducing hair growth.

Finasteride may be suggested as part of gender-affirming hormone therapy (GHAT), particularly in the early stages. However, there are some unique considerations for trans women thinking about taking finasteride.

Combination with Other Hormone Treatments

Transgender women undergoing hormone replacement therapy (HRT) may be on estrogen therapy (oral estradiol) and possibly antiandrogens like spironolactone. 

Finasteride can be used as part of this regimen to further reduce the effects of androgens. However, some research suggests that finasteride for transgender women is not all that effective once testosterone levels have already been lowered with standard treatment regimens, including estrogen with spironolactone or cyproterone acetate.

Some research actually suggests that the use of finasteride makes it challenging to achieve adequate testosterone suppression with estrogen, which is something to consider.

Finasteride Side Effects

We mentioned this above, but finasteride can have side effects. These are rare and typically resolve spontaneously.

You can learn more about the side effects of finasteride in our post on the topic.

Medical Supervision

It's crucial for transgender women to use finasteride under the supervision of a healthcare provider. The provider can monitor hormone levels and adjust dosages as needed. 

Can trans men grow facial hair on finasteride?

The hair follicles on the face aren't as affected by DHT as those on the scalp, and for this reason, finasteride typically does not impact facial hair. 

However, another FDA-approved medication for hair loss, minoxidil, is more effective at growing facial hair. You can learn more in our guide to minoxidil beard growth.

Does finasteride grow chest hair or body hair?

Finasteride is known to promote scalp hair, but just as with facial hair, the medication does not affect body hair because body hair follicles aren’t nearly as sensitive to DHT. All this to say, research shows that finasteride is not likely to have much of an effect on chest or body hair growth.

Instead, testosterone is usually offered to trans men as part of gender-affirming care. The effects of testosterone can include increasing body and facial hair growth and making existing hair thicker and coarser.

Does finasteride affect male breasts?

As we note, gynecomastia, or the development of male breast tissue, is a (very) rare but possible side effect. According to some research, only eight cases of gynecomastia have been reported with low-dose (1 mg daily) finasteride treatment since its approval for androgenetic alopecia in 1997. But this is likely under-reported.

In clinical trials of finasteride, a very small percentage of men developed male breast cancer (sometimes called male breast neoplasia), which also occurred in several men in the placebo group. As such, it’s unclear to what extent, if any, finasteride played a part in male breast neoplasia.

However, if you notice breast tenderness or nipple discharge, it’s very important to seek medical care as soon as possible.

Because transgender people have different goals, there isn’t one best hair growth treatment that works for everyone. Below are a few alternative hair loss treatments.

Minoxidil

We touched on minoxidil briefly in the context of beard growth, but here’s the deal for hair loss. Minoxidil (the active ingredient in Rogaine®) is a popular and effective hair loss medication that doesn’t affect hormones. It can be a great option for those wanting to treat hair loss without hormonal changes.

We offer both a minoxidil foam and a minoxidil solution, or you can find the ingredient in combination with finasteride in our topical finasteride and minoxidil spray. Following a consultation with one of our healthcare professionals, oral minoxidil (which, unlike its topical counterpart, is not over-the-counter) may also be available.

Spironolactone

Spironolactone is the most commonly used antiandrogen treatment for female pattern hair loss in the U.S., and it’s also widely used in hormone therapy for trans women. It’s not usually recommended for men or trans men due to its feminizing side effects.

Spironolactone is frequently used by transgender women as part of gender-affirming hormone therapy (GAHT). By blocking male sex hormone receptors and reducing testosterone levels, it can contribute to the development of feminine characteristics, such as facial feminization and breast growth.

Saw Palmetto

If you’re interested in something similar to finasteride but plant-based, there’s some evidence that the botanical ingredient, saw palmetto, also inhibits DHT. You can find it in our thickening shampoo with saw palmetto.

There’s a lot to consider when it comes to the use of finasteride by transgender people. Here’s a quick recap:

• Finasteride is part of a class of drugs called 5α-reductase inhibitors, which stop the conversion of testosterone to DHT. It can be a valuable component of gender-affirming therapy for trans men and trans women. It works as a treatment for pattern hair loss but can also help with the reduction of unwanted body hair.

• It's crucial for transgender individuals considering finasteride to do so under the guidance of a healthcare provider to monitor its effects, manage potential side effects, and adjust treatment plans as necessary. Finasteride can and does affect hormones, and it should always be used under medical guidance.

• Since the best hair growth treatment varies based on personal goals and health conditions, transgender patients should consult healthcare professionals to explore options like minoxidil, finasteride, spironolactone, and other alternatives tailored to their specific needs.