Finasteride Side Effects in Women

If you’ve started noticing the signs of hair loss, you’re not alone — and you’re also not doomed. Treatments like finasteride can help slow down hair loss. But before you ask for a prescription, it’s good to learn about potential finasteride side effects in women.

Roughly 40 percent of women develop female pattern hair loss (FPHL) by age 50. FPHL is also sometimes called female pattern baldness, androgenic alopecia, or androgenetic alopecia.

FPHL is a hormone-related condition that can lead to permanent hair loss. Fortunately, though, there are some ways to slow down FPHL and prevent further hair loss.

One possible hair loss treatment is finasteride. But the adverse effects that could occur shouldn’t be overlooked. Here’s what to know about the finasteride side effects women might experience.

Finasteride is currently approved by the U.S. Food and Drug Administration (FDA) to treat male pattern baldness and benign prostatic hyperplasia (BPH).

While the FDA hasn’t approved finasteride for use by women, it can still legally — and effectively — be used to combat female pattern baldness. This is an off-label use, meaning a healthcare professional prescribes it for something it’s not FDA-approved to treat.

If you’re interested in taking oral or topical finasteride, you should understand the potential risks. Let’s look at finasteride side effects in women, how to take the hair loss medication safely, and alternatives to finasteride for women.

Also sold under the brand name Propecia®, finasteride is a prescription hair loss treatment. As mentioned, it’s also used to treat benign prostatic hyperplasia, a condition where you develop an enlarged prostate gland. 

To understand how finasteride works, you need to first know a bit about female and male pattern hair loss.

Although testosterone is considered an androgen (male hormone), everybody has some testosterone in their bodies. Testosterone has critical functions in both men and women.

Some testosterone is converted into a different hormone called dihydrotestosterone (DHT). DHT can attach to androgen receptors in the scalp, which shrinks hair follicles. Over time, hair becomes thinner — and eventually, it’ll struggle to grow altogether.

How Finasteride Treats Hair Loss

So, where does finasteride come into all this? Finasteride is a 5-alpha reductase inhibitor (aka 5ARI). It blocks the 5-alpha reductase enzyme that’s involved in the conversion of testosterone into DHT. As a result, finasteride lowers DHT levels. 

With lower levels of DHT in the scalp, the hormone won’t damage your hair follicles at such a rapid rate. This slows down DHT-related hair loss.  

Oral finasteride is the most common form of this medication. There’s also a topical version. Though it’s not FDA-approved, topical finasteride has shown to be an effective treatment for hair loss.

Although not FDA-approved for women, clinical trials show that finasteride can be particularly helpful for the treatment of female pattern hair loss in pre- and postmenopausal women.  

In one small study with 37 women, 62 percent of participants saw some reduction in hair loss and improved hair density after taking a 2.5-milligram (mg) oral dose of finasteride for a year. One thing to note: These women also took birth control pills, making it impossible to solely attribute the hair growth to finasteride. 

Another study focused on 87 pre- and postmenopausal women taking 5 milligrams a day of oral finasteride for over a year. By the end of the study, most of the women noticed denser hair.

It’s worth noting the dosage of finasteride in both of these studies — 2.5 and 5 milligrams daily. There was a study published in 2000 in which 137 postmenopausal women with FPHL took only 1 milligram a day of oral finasteride and didn’t notice any benefits.

These studies of successful finasteride use in women are small, and more research absolutely needs to be done. Still, they suggest finasteride could effectively treat FPHL.

But you may be wondering, Is finasteride safe for women? We have more insight below. 

Topical finasteride seems to be safer for women than oral finasteride. Topical finasteride may cause some side effects, but these are generally mild — like an itchy scalp.

Research shows that low-to-medium doses of oral finasteride are, for the most part, well-tolerated by postmenopausal women.

Oral finasteride side effects in women can be more of an issue. These include:  

• Sexual dysfunction (e.g., low sex drive)

• Irregular menstruation

• Acne

• Headaches

• Dizziness

• Folliculitis (inflamed hair follicles)

• Increased body hair growth

Rarely, oral finasteride causes more serious adverse effects in women, such as:

• Increased breast tenderness 

• Breast enlargement, lumps, and pains

• Allergic reactions (characterized by hives, face swelling, difficulty swallowing, and difficulty breathing)

Again, those are the side effects associated with oral finasteride, not the topical formulation. If you take finasteride and experience any of these things, contact a healthcare professional right away.

One last disclaimer: If you’re pregnant or planning to conceive, you shouldn’t use finasteride at all — oral or topical. Since it affects testosterone levels, the use of finasteride can cause congenital abnormalities (birth defects), particularly in male genitalia.

If you’re considering hair loss treatments but you’re concerned about the potential for finasteride side effects in women, we’ve got your back. 

Many hair loss treatments for women are out there, including:

• Minoxidil. Topical minoxidil — like minoxidil solution and minoxidil foam — is FDA-approved to treat female pattern baldness. It works by slowing down hair loss and stimulating hair regrowth. You can also try oral minoxidil, which isn’t FDA-approved for hair loss.

• A combo of minoxidil and finasteride. If you want a topical treatment that packs a real punch, our topical finasteride & minoxidil spray is a great choice. Designed for postmenopausal women, the treatment is simply sprayed onto the thinning parts of the scalp to promote hair growth.

• Hair growth supplements. Your body needs nutrients to produce hair cells. If you have a nutritional deficiency, you might experience hair loss. Eating a balanced diet and using a supplement like our biotin gummies can help your scalp recover.

• Quality hair care products. Besides keeping your hair and scalp clean, hair care products can improve the appearance of thinning, limp hair. Try our volumizing shampoo and volumizing conditioner.

Not sure which hair care treatment to choose? Your best bet is to make an appointment with a healthcare professional. They can assess your hair loss and help you navigate treatment options.

Finasteride is FDA-approved to treat male pattern baldness — not female pattern hair loss. Some research shows it can help women, too, but there are potential finasteride side effects for women. 

Here’s what you should know:

• Finasteride treatment can curb pattern baldness. It does this by blocking DHT, a hormone that damages hair follicles.

• Women should opt for topical finasteride. Compared to oral finasteride, topical finasteride is associated with fewer side effects for women. Pregnant women should avoid finasteride altogether.

• There are alternatives to finasteride for women with hair loss. These hair loss treatments include minoxidil, supplements, and quality hair care products.

Worried about your widening hair part or thinning hairline? The first step is to connect with a healthcare professional. They can give you personalized medical advice and guide you through your treatment options for hair loss. 

This article is for informational purposes only and does not constitute medical advice. The information contained herein is not a substitute for and should never be relied upon for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment. Learn more about our editorial standards here.