Does Finasteride Cause Erectile Dysfunction?

If you’re looking for an effective hair loss treatment, you’ve probably already heard about Propecia and some of the potential side effects associated with finasteride, the main ingredient in Propecia, Proscar, and other products.

Propecia is the lower dose version of finasteride that treats male pattern hair loss, also called androgenetic alopecia. Proscar is the higher dose version of finasteride medication prescribed for benign prostatic hyperplasia (BPH), a condition known informally as enlarged prostate.

Long term erectile dysfunction (ED) and other types of sexual dysfunction are among the most concerning possible adverse effects of finasteride contained in either medication. is. The risk of these complications is low, however. And post-finasteride sexual dysfunction often may be treated effectively with a variety of brand name ED medications, such as Viagra, Cialis, Levitra, or Stendra or their generic counterparts.

Below we explore the benefits of finasteride, as well as its side effects. We’ll also explain how the medication may cause ED and what you can do about it.

An estimated 50% of adults experience some form of androgenetic alopecia. It may be mild, with relatively little hair loss, or much more severe. A review of hair loss treatments found that finasteride is most effective when androgenetic alopecia is in its early-to-moderate stage and when it’s progressing, rather than after complete hair loss.

Finasteride is part of a class of drugs called 5-alpha reductase inhibitors. They were originally approved to treat benign prostatic hyperplasia (enlargement of the prostate). Another example is dutasteride, which may also be helpful in treating urination difficulties brought on by BPH. 5-alpha reductase inhibitors were later found to be effective treatments for male pattern baldness.

Finasteride is not recommended for causes of hair loss that don’t include androgenetic alopecia. These include conditions such as:

• alopecia areata (an autoimmune condition)

• blood pressure medications (some commonly used antihypertensive drugs lead to hair shedding)

• nutritional deficiencies

• stress

• thyroid disease

Finasteride is a generally well-tolerated and safe medication. The FDA-approved oral formulation of finasteride to treat androgenic alopecia is a 1 milligram (mg) tablet. When finasteride is prescribed for BPH, the dose is usually a 5 mg tablet. You can take the medication with or without food, and it’s recommended to be taken at about the same time each day.

Topical finasteride is also available as a spray, and is sometimes combined with minoxidil, a widely used liquid treatment that helps slow baldness.

If finasteride is going to be effective, you should expect to start seeing some improvement within three months or so, with more substantial effects visible within 12 months. This is because hair growth and hair loss take time and each person’s hair growth timeline is different.

Its primary benefit is to slow or halt the loss of hair due to male pattern baldness. Men under the age of 40 may experience an improvement all over the scalp, including the crown, hairline, and around the temples. Older men are more likely to see improvements just on the crown and the area just in front of the scalp.

But some users actually experience some hair regrowth. Research suggests that some users of oral finasteride may experience a 10% increase in hair growth within a year — exciting stuff!

Keep in mind that finasteride is only effective if taken every day. With discontinuation of the medication, hair loss may start up again. Similarly, finasteride for BPH is helpful only as long as you take the medication.

In rare cases, some individuals may lose hair and experience persistent sexual side effects and other complications soon after starting on finasteride. It’s part of a condition called post-finasteride syndrome, and it may cause some symptoms to linger even after stopping the medication.

The FDA, which approved finasteride for male pattern baldness in 1997, notes that the medication includes several possible side effects. Among them are:

• brain fog

• depression

• gynecomastia (male breast tissue enlargement) and an increased risk for breast cancer

• rash

• swelling of the face and lips

• testicular pain

The FDA also acknowledges that finasteride may contribute to several sexual side effects, including decreased libido (sex drive), lower ejaculation volume, and erectile dysfunction. However, the risk of finasteride side effects is fairly low. Only about 1.3% of individuals using Propecia for male pattern baldness experience ED. The rates of ED for patients with BPH that take Proscar, which contains higher doses of finasteride than Propecia, are higher. One study reported found that the risk of ED with high dose finasteride treatment is about 8%.

Sexual side effects are possible with both oral and topical finasteride, though a study of 458 finasteride users found that topical finasteride was similarly effective in treating hair loss compared with the oral medication, but with fewer adverse events.

For most patients, ED and other sexual problems that develop during finasteride therapy resolve with treatment cessation. However, there is a very small subset of patients who report persistent and difficult-to-treat sexual side effects after taking finasteride. There is controversy in the medical community about this condition. Some experts very much believing that finasteride may very rarely cause permanent sexual dysfunction in susceptible people. Other experts believe that many or all of the patients who report persistent post finasteride sexual dysfunction may be suffering from other causes of psychogenic or organic ED that are not related to finasteride. Regardless of the underlying cause, there is widespread agreement that permanent post-finasteride sexual dysfunction is exceedingly rare and that finasteride is safe for the vast majority of patients that take it.

Finasteride and other 5-alpha reductase inhibitors work by reducing dihydrotestosterone (DHT) levels in the body. 5-alpha-reductase is an enzyme that converts testosterone — the primary male sex hormone — into a more potent hormone called DHT. 5-alpha reductase inhibitors are also known as DHT blockers.

DHT is a key hormone in male sexual development. But for individuals genetically predisposed to male pattern hair loss, DHT serves a less helpful function. DHT binds to androgen receptors in the scalp and causes hair follicles to gradually stop producing new hairs.

DHT also supports the enlargement of the prostate, which is why taking a DHT blocker can shrink the prostate and effectively treat BPH.

Though finasteride doesn’t completely eliminate DHT from the body, it is often effective enough to halt androgenetic alopecia. Lowering DHT levels throughout the body, though, can impact sexual function in some people for reasons that are not completely understood. This probably relates to the fact that even though DHT is not the main male sex hormone, it does have some testosterone-like activity in certain parts of the body and brain.  While this doesn’t effect most people who take finasteride, some people do experience sexual problems when they take Propecia or Proscar.

The good news is that the vast majority of people that take finasteride for hair loss do not experience sexual side effects. However, the risk of finasteride causing ED is not zero. Before you start taking it, talk with your healthcare provider about how to use finasteride safely and about all the potential benefits and adverse side effects. Making an informed decision, with your doctor or another healthcare professional, will help you feel more confident about your choice and prepare you for what’s ahead.

If you start using finasteride and experience no side effects, but enjoy benefits like a halt to your receding hairline or even some hair regrowth, then consider using the medication indefinitely to maintain your hair health. If you do experience sexual side effects, it is best to stop taking the medication and connect with your medical provider to discuss alternative treatments.