Getting Started Using Finasteride for Hair Loss

Written by Adrian Blackwell, MD

What kind of side effects does finasteride have? Is finasteride safe to use?

What are the side effects of finasteride?

The good news here is that potential side effects of finasteride are not common, are mostly pretty mild, and will for the most part go away if you stop taking it. Fewer than 1% of men have to experience the side effects below while taking finasteride:

  • Erectile Dysfunction (0.6%)
  • Decreased libido (0.5%)
  • Decreased volume of ejaculate (0.4%) - does not negatively impact sexual function in and of itself
  • Depression (< 1%)
  • Allergic reactions (< 1%)

There are some other reported side effects for finasteride. These side effects seem to be a problem for men who are taking the higher dose of finasteride that is used to treat prostate problems (5mg for prostate enlargement, 1mg for hair loss treatment). The side effects linked to higher doses of finasteride are still very uncommon, but could include:

  • Breast changes (discharge from the nipple, lumps, enlargement, and tumors)
  • Male breast cancer (very rare association)
  • Testicular pain
  • In men over the age of 55 years old, using 5mg of finasteride for an enlarged prostate, it might cause an aggressive type of prostate cancer ( 0.7%)

What should I do if I experience side effects from finasteride?

If you experience side effects from finasteride, pause your use of this medicine and talk to your doctor. It might mean that this medicine is not right for you and you may need to think about different ways to treat your hair loss.

In some cases, the side effects will lessen over time. That is why some men, under the guidance and care of a physician, choose to keep taking the medicine and treat the side effects instead of stopping finasteride altogether (e.g. some men take Viagra for the side effect of erectile dysfunction.)

The bottom line here is you must talk with your doctor if you are on finasteride and start having problems. Your doctor can help you figure out a plan that is right and safe for you.

How long do I have to take finasteride before my hair gets better?

Finasteride is a long term medication. It needs to be taken daily for 3 months, at least or sometimes longer, to see improvements in hair growth. It’s really important to take the medication every day and make sure that you have plenty of refills.

Am I going to have to take finasteride forever to keep my hair?

If you stop taking finasteride, your hair growth and positive changes will go away within 12 months. If you are having good results using finasteride, you may have found a friend for life! In addition, the longer you take finasteride, the better results you will have over the long term. On the flip side, almost all side effects will also go away when you stop taking the medicine. If you’re concerned about having to take finasteride forever, make sure to talk with a doctor.

Can I use minoxidil (aka Rogaine) and finasteride at the same time?

Yes! The good news is that finasteride does not have a lot of important or dangerous interactions with other drugs like some medicines do. You can safely take minoxidil and finasteride together at the same time. They work in different ways to help you keep your hair. And you can get the minoxidil over the counter.

Can I use 5mg finasteride pills and just split them into four smaller pieces for hair loss?

There are some doctors who may prescribe you the higher 5mg finasteride pill to help you save on cost for hair loss. However, the FDA has only approved 1mg finasteride for hair loss. If you split a 5mg pill into four pieces you will be taking approximately 1.25mg instead of the recommended 1mg. Additionally, it can be challenging to split pills evenly when splitting them into four pieces so you may actually be taking less than 1mg in some doses.

Can I use oral minoxidil (pills) for hair loss instead of the topical, over the counter form?

Minoxidil in pill form is not used to treat hair loss, and it’s not FDA approved for that purpose - so it’s not a good idea.

The views expressed in this article intend to highlight alternative studies and induce conversation. They are the views of the author and do not necessarily represent the views of HeyDoctor, and are for informational purposes only, even if and to the extent that this article features the advice of physicians and medical practitioners. This article is not, nor is it intended to be, a substitute for professional medical advice, diagnosis, or treatment, and should never be relied upon for specific medical advice.

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