Finasteride vs Dutasteride: 3 Things to Know Before You Get Started

Dr. Patrick Carroll, MD
Medically reviewed by Patrick Carroll, MD Written by Our Editorial Team Last updated 9/19/2019

Many of the effective treatments for male pattern baldness work by blocking the conversion of dihydrotestosterone (DHT) from testosterone in the scalp. For those who don’t know, DHT is strongly linked to hair loss and is believed to be the primary reason why the majority of men experience androgenic alopecia (male pattern baldness) at some point in their lives.

When it comes to treating hair loss, there are a number of products on the market that are thought to work by disrupting DHT. You can find treatment in the form of supplements like biotin, DHT-blocking shampoos containing ketoconazole or pyrithione zinc and pharmaceutical medications that act as 5α-reductase inhibitors (aka 5-ARIs). 

Of these treatments, finasteride (also sold under the brand name Propecia®) is the only prescription medication that’s been approved by the FDA to treat male pattern baldness, which is why so many men have been able to benefit from its ability to combat hair loss.

Perhaps you’ve heard of another 5-ARI called dutasteride. It’s a type of DHT-blocking medication that works similarly to finasteride, and while it has been approved in some Asian countries to combat male pattern baldness, it hasn’t been approved by the FDA for hair loss in the US. It has only been approved as a treatment for benign prostatic hyperplasia (more commonly known as BPH)

This begs the question: is dutasteride as effective and safe as finasteride?

Is Dutasteride as Effective as Finasteride?

Dutasteride has proven itself an effective treatment for male pattern baldness. In one study, researchers tested the effects of finasteride vs. dutasteride on 917 men between the ages of 20 and 50 who were at various stages of male pattern baldness. 

They concluded that both finasteride and dutasteride were successful at increasing hair growth over a 24-week period, and that side effects were similar among both groups. It is worth noting that although finasteride and dutasteride were each successful at promoting hair growth, the study concluded that dutasteride produced thicker hair — and more of it — after 24 weeks than finasteride. 

In another study, researchers looked at 399 patients and found that dutasteride blocked more than 90 percent of DHT, while finasteride blocked around 70 percent. 

Dutasteride may also be more effective at promoting hair growth. In a 2006 study, 416 men between the ages of 21 and 45 were given dutasteride, finasteride or a placebo over a span of 12 to 24 weeks. The researchers found that dutasteride actually produced better hair count results based on the summary of an expert panel who looked at before and after photos. 

In a review of studies of both finasteride and dutasteride for the treatment of BPH, scientists determined that dutasteride reduces more DHT than its counterpart.

However, while dutasteride has been shown to be effective, it’s also worth noting that finasteride is currently the only prescription medication approved by the FDA for treating male pattern baldness. That means finasteride has undergone — and passed — the FDA’s rigorous drug approval process and shown that it’s safe and effective for the treatment of hair loss in men.

If you want to know more about dutasteride’s efficacy in treating male pattern baldness, it’s always best to discuss this with your doctor. 

Finasteride and Dutasteride Both Have a Risk of Sexual Side Effects (Though Rare)

Just like with finasteride, individuals taking dutasteride may experience negative sexual side effects like decreased libido, erectile dysfunction and problems ejaculating. 

In one study, researchers found that 5.1 percent of men who used dutasteride stopped taking it due to some sort of sexual dysfunction as a result of their treatment. 

In addition, the study also found that 3.5 percent of men taking dutasteride also experienced tenderness in the breast or gynecomastia — the enlargement of breast tissue.

Finasteride vs Dutasteride: The Choice

Most of the research around dutasteride has verified that it is an effective way to treat male pattern baldness. 

However, it isn’t approved by the FDA to treat hair loss in men. Of course, this doesn’t mean that it’s ineffective at fighting male pattern baldness, but that the drug hasn’t been evaluated by the FDA to determine that it’s effective and safe for treating male hair loss.

At the end of the day, there are a few things to consider before taking dutasteride to treat your hair loss problem. Ultimately, it’s up to you and your doctor to decide what drug is best for you.

If you’d like to learn more about how finasteride can help in the fight against male pattern baldness, talk with your primary physician or dermatologist. They can help you determine whether a 1mg dose of finasteride is right for you.

Everything you need to keep the hair on your head. If you're into that. Try hims for $5.

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.