If you’ve ever searched the internet for hair loss solutions, you’ve probably come across dozens of articles about finasteride—and for good reason. Finasteride works to block the conversion of testosterone to dihydrotestosterone (DHT), the hormone responsible for causing male pattern baldness. It’s also one of the two FDA-approved treatment options for hair loss.

Typically, finasteride is administered orally via small tablets. However, recent studies suggest that topical finasteride may have fewer side effects, with many of the same benefits as the traditional tablets.

Let’s take a closer look at what topical finasteride is, the potential side effects, and how you can use it to treat hair loss.

What, exactly, is topical finasteride?

This is actually a more complicated question than you might imagine.

There are two qualities that you’ll find in any treatment that includes a topical finasteride dosage. The first thing you’ll notice is that topical finasteride comes in a liquid form. Beyond that, you’ll likely purchase it either as a spray, finasteride gel, or droplet form.

Sounds straightforward, right? It sure does. But if you want to get into the weeds of topical finasteride, it’s important to know that it’s typically administered in concert with other ingredients known to promote hair growth. Most often, you’ll find that topical finasteride treatments include minoxidil. Minoxidil is an FDA-approved hair loss treatment that helps to stimulate hair growth.

Does topical finasteride have side effects?

Many individuals who use topical finasteride see equal results to those who use the traditional tablets. Studies indicate that oral finasteride side effects may still apply to topical finasteride—but often they impact people at a lower rate than oral finasteride.

To review, here’s a list of the side effects associated with finasteride:

  • Depression or anxiety
  • Dizziness, weakness, or feeling like you might pass out
  • Headache
  • Inability to urinate
  • Pain in the testicles
  • Runny nose
  • Rash
  • Signs of an allergic reaction like skin rash, itching, difficulty breathing, swelling of the face, lips, or tongue
  • Sexual side effects (more on that below)
  • Swelling in your hands or feet
  • Swelling, pain, or tenderness in the breasts, or fluids leaking from the nipple

We spoke to Keeps Medical Director, Dr. Peter Young, to better understand how oral and topical finasteride affect people differently. He described that topically applied medications are absorbed less into your system (blood circulation) than oral medications, and therefore have less potential to cause systemic side effects. In fact, many clinical studies have shown that the topical form of finasteride may have a lower risk of sexual side effects, such as erectile dysfunction, than the pill form.

Therefore, if you have experienced sexual side effects from oral finasteride or are concerned about this side effect, the topical formulation of finasteride may provide the same benefits for your hair loss as the oral version with a lower chance of these side effects.

In rare cases, men may experience localized skin reactions such as itching, burning, dryness or flaking if they are allergic or sensitive to ingredients included in topical finasteride. These reactions usually resolve shortly after the medication is stopped.

Some men may experience temporary hair shedding during the first two months of treatment. This occurs as a result of the minoxidil stimulating thinning hairs to fall out and make way for new, healthier hair. Any increased hair loss is just a sign that your “bad” hair is making way for your “good” hair.

How long does topical finasteride take to work?

Studies suggest that men who use topical finasteride will experience results such as increased hair regrowth and decreased hair loss within four to six months of starting treatment. While it is likely to see new hair growth in as early as four months of starting treatment, most individuals see the biggest improvement in hair growth after 12 to 18 months of using topical finasteride.

What happens if I stop applying topical finasteride?

Even though topical and oral finasteride are different types of medications, the outcome of not using it is the same. You’ll either use it, or lose it.

The half-life of finasteride in any form is relatively short. What does that mean in layman’s terms? The benefits of finasteride will likely leave your system within just a few days of stopping treatment. When finasteride is out of your system, you should expect to see your previous rate of hair loss return.

In a previous guide, Keeps medical advisor Dr. Raman Madan explained that without finasteride, your body will not be able to block 5α-reductase. This is the enzyme that converts testosterone into DHT. And while we’ve reviewed the shortlist of potential side effects, Dr. Madan emphasizes that it’s safe to take finasteride for long periods of time to maintain results.


To recap: Finasteride is one of the only tried-and-true treatments for folks looking to treat hair loss. By combining it with minoxidil, which is proven to help stimulate hair regrowth, you may be able to treat male pattern baldness more effectively.

If you’re looking to stop hair loss and promote new hair growth, topical finasteride might be the best treatment option. Research has shown it to be one of the most effective ways for men to fully address the symptoms of hair loss.

Stay tuned to find out when this treatment option will be available through Keeps.

The information provided in this article is not a substitute for professional medical advice, diagnosis, or treatment. You should not rely upon the content provided in this article for specific medical advice. If you have any questions or concerns, please talk to your doctor.

Photo by Malte Helmhold via Unsplash