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Dec 8, 2024

What is Finasteride? How it Works, Side Effects and Benefits

Hair today, gone tomorrow — not so fast...

With up to 50% of men experiencing hair loss by age 50, it’s no wonder many men are seeking hair loss solutions.

One popular option is finasteride, an oral medication used to treat hair loss and other conditions. There’s a good chance you have a lot of questions about this medication, which is where we come in.

Here’s what every man should know about finasteride, from its benefits to its uses and everything in between.

What is finasteride?

Finasteride is a 5-alpha reductase inhibitor. It works by blocking the 5-alpha reductase enzyme from changing testosterone into DHT. This reduces the amount of DHT in your body and protects hair follicles from further damage and slows hair loss.

DHT is produced when the enzyme 5-alpha reductase converts testosterone. DHT binds to receptors in your hair follicles and causes them to shrink. This can lead to hair thinning and hair loss, especially around your hairline or at the top of your head.

In simpler terms, an enzyme known as 5-alpha reductase turns testosterone into dihydrotestosterone. Too much DHT can cause hair loss. Finasteride blocks 5-alpha reductase and lowers the amount of DHT. Your hairline reaps the benefits.

While DHT contributes to hair loss, it also plays other important roles in the body, like supporting sexual development and prostate growth.

What is finasteride used for?

Finasteride is FDA-approved to treat two conditions: male pattern baldness and enlarged prostate (also known as benign prostatic hyperplasia).

To treat hair loss, people are often prescribed a 1mg tablet that’s taken daily. As an alternative to oral tablets, Finasteride is also available in a topical spray solution. Although this application is not FDA-approved, there is research to show it effectively treats hair loss.

Is finasteride effective?

Can finasteride prevent you from looking like Lex Luthor or Vin Diesel? While this may not seem like such a bad thing for some men, for the ones who want to grow hair back finasteride works to treat several types of hair loss, and there’s research to back it up.

In one study, 90% of men with hair loss who took oral finasteride over a period of five years experienced improved hair growth or maintained their current amount of hair.

And according to a study published in the Journal of the American Academy of Dermatology, men with male-pattern baldness who were treated with finasteride experienced a significant increase in their hair count and/or a slowed progression of hair loss.

Oral finasteride vs. topical finasteride

Wondering if oral finasteride or topical finasteride is more effective?

One study comparing topical finasteride with the oral version found the topical solution to be nearly as effective in increasing hair growth when used over a period of 24 weeks.

Ultimately the choice between oral or topical finasteride comes down to preference, your type of baldness, and desired results.

Oral finasteride offers a more generalized holistic regrowth, while topical finasteride allows you to specifically target certain areas of the scalp that might need a little help.

Are there finasteride side effects?

Like many medications, there is a possibility of experiencing side effects when taking finasteride.

The good news is that many finasteride side effects are mild and manageable. Finasteride side effects may include:

  • Reduced sexual desire
  • Trouble getting an erection
  • Problems ejaculating
  • Depression
  • Testicle pain


While there are some sexual side effects, they are rare and treatable. Options include erectile dysfunction medications to therapy and counseling.

Taking finasteride can also increase the risk of developing high-grade prostate cancer. However, this severe side effect happens from a higher dosage of 5 mg than the typical 1 mg finasteride dose used to treat hair loss.

How quickly does finasteride work?

There’s always the hope that any medication solves the issue right away, but good things take time. The same is true with finasteride for hair loss.

While you won’t see results from finasteride overnight, there can be a 65% reduction in serum DHT levels within the first 24 hours of taking the medication.

More visible results from daily finasteride use usually take about three to six months. In a 2004 study of over 400 Japanese men with hair loss, the subjects saw “significant improvement” after three months of taking finasteride. Typically, people see results after a year.

But everyone’s hair growth journey is different and you may not see any noticeable results. If this is the case after using finasteride for 12 months, there are other hair loss treatments that could offer different results. The key is determining which one is best for you.

Can finasteride be used with other drugs?

If you’re eager to experience finasteride benefits quickly, you may think of combining the drug with other medications. But does finasteride work well with other hair loss treatments? And can combining finasteride with other hair loss treatments speed up your results?

Combination treatment solutions can be effective — depending on the type of hair loss you may be experiencing, its severity, your health history, and other factors. For example, finasteride can be combined with the topical hair growth medication minoxidil for an effective treatment that may prevent further hair loss and promote new hair growth.

The final word on finasteride?

Finasteride offers benefits when taken for at least a few months to treat hair loss. Whether or not you should use finasteride depends on several factors.

While finasteride has been proven safe and effective, there’s a possibility of experiencing side effects, though these tend to be minimal and manageable.

Dealing with hair loss isn’t fun, but it can be easy. If you’re one of the many men seeing less and less of your hair with each passing day, finasteride is one solution for a fuller head of hair.

References:

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  3. FDA Drug Safety Communication: 5-alpha reductase inhibitors (5-ARIs) may increase the risk of a more serious form of prostate cancer. (2018, February 08). U.S. Food & Drug Administration. https://www.fda.gov/drugs/drug-safety-and-availability/fda-drug-safety-communication-5-alpha-reductase-inhibitors-5-aris-may-increase-risk-more-serious
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