What’s the Difference Between Propecia and Finasteride?

February 5, 2023 Dr. Steven Shapiro

If you’ve done any research on hair loss remedies, there’s little doubt you’ve seen the names Propecia® and finasteride.

It may have you wondering: what’s the difference between Propecia vs finasteride? Simply put, finasteride is the generic form of Propecia. The brand contains the active ingredient finasteride, as do generic forms. Propecia and finasteride are different recipes for the same active and effective men's hair loss medication.

What Is Finasteride?

Finasteride is a synthetic drug used to treat men with benign enlarged prostates and male-pattern baldness. It’s a chemical compound known as a 5-alpha reductase (5AR) inhibitor. By inhibiting this enzyme, finasteride reduces the amount of testosterone converte to dihydrotestosterone (DHT), a hormone that contributes to male pattern baldness in people who are susceptible to the condition, generally due to genetics or inherited traits.

DHT and Androgenic Alopecia

Androgenic alopecia is the medical term for male and female pattern baldness. Your body produces male sex hormones (yes, even women have these) known as androgens. Two of the primary androgen hormones are testosterone and dihydrotestosterone (DHT). Everybody has heard of testosterone, but not everyone knows what DHT is, despite that it’s one of the most powerful androgens and contributes meaningfully to males’ traditionally masculine features.

DHT is derived from testosterone. An enzyme known as 5-alpha reductase converts some of your testosterone into DHT. This takes place in androgen receptors located in various parts of the body, including the hair follicles.

DHT can also bind with these androgen receptors, which can lead to follicle shrinkage and hair loss. People who are genetically predisposed to androgenic alopecia have high rates of DHT-binding, which leads to weaker, shrinking hair follicles.

DHT is one of the core causes of androgenic alopecia and hair loss in men and women. Here at Shapiro MD, we often call it the hair loss hormone.

Finasteride and Androgenic Alopecia

Finasteride interacts with the 5-alpha reductase (5AR) enzyme, which comes in two isotopes: Type I and Type II. The drug impacts only the Type II isoform, but this form is responsible for the creation of about two-thirds of the DHT circulating in your body. By reducing the 5AR in your body, finasteride/Propecia can limit how much DHT occurs through the conversion of testosterone. It’s a creative way to reduce DHT in the body.

Finasteride does not interact with your androgen receptors; its impact on hair growth and loss is due to the suppression of DHT production.

This chemical compound acts fast, reducing the amount of the hormone in soft tissues and blood by 65% within a day of taking a 1-milligram tablet, and by 80% or more over time. This reduction has been shown to slow and stop hair loss in men, and even help to regrow denser hair.

What’s the Story On Propecia?

Propecia is a drug created by the pharmaceutical giant Merck. The active ingredient in the drug is finasteride. Merck is the company that originally developed finasteride.

History of Finasteride

In the mid-1970s, Merck began investigating how to create a drug that would lower DHT levels after scientific observations revealed that a reduction in DHT led to smaller prostates. The hope was that they could create a drug that would treat enlarged prostates in men. The scientists at the company experimented on various forms of potential 5-alpha reductase inhibitors.

The first drug approved to reduce DHT levels was Proscar. The U.S. Food and Drug Administration gave it the green light in 1992 to treat benign prostatic hyperplasia. The medication is prescribed in 5-milligram doses.

Five years later, the USDA approved finasteride in a 1-milligram dose to treat androgenic alopecia in men. It was marketed under the label Propecia. These two drugs were the first-ever 5-alpha reductase inhibitors.

For years, Propecia and Proscar were available as branded medications only. As the first and only oral medication for male hair loss, Propecia was a big success. It’s helped millions of men improve their hair.

Now, finasteride is available in generic forms at much lower prices than branded Propecia, including through Shapiro MD.

Usage and Dosages for Finasteride

Propecia is used for the treatment of androgenic alopecia in men only. It is available in tablet form, with each one containing 1 milligram of finasteride. The recommended dosage is once per day. It may take a few months before you see results, and continued use is recommended. Men who stop taking the drug may see a reversal of benefits within a year after stopping.

Side Effects of Finasteride

The potential for side effects is low; however, as with any drug, you need to be aware of them before you begin taking finasteride. In 2012, the USDA released information about potential side effects that were then included on the label for finasteride medications. Possible adverse reactions include:

Erectile dysfunction and decreased libido
Ejaculation or orgasm disorder
Poor seminal quality or infertility
Testicular pain
Breast tenderness and enlargement
Breast cancer
Sensitivity reactions that include rashes, urticaria, pruritis and swelling in the face and lips
Depression

Thus far, there are no known drug interactions.

Clinical Trials of Finasteride for Men

To determine the effectiveness of finasteride on male pattern hair loss, Merck conducted three clinical trials: two on men with hair loss at the crown and one on men with hair loss in the anterior, mid-scalp region. Each of these lasted 12 months. Scientists used a randomized, double-blind approach, where participants received either finasteride or a placebo, and neither the administrators nor the participants knew who got which dose. The participants were all men between the ages of 18 and 41 who had mild to moderate androgenic alopecia.

The results of the trials indicated that Propecia is very effective in treating male-pattern baldness. The men who participated in these students saw positive results within three months of beginning treatment. After 12 months, only 14% of the men treated with Propecia demonstrated further hair loss, compared to 58% of the men in the placebo group. Furthermore, the men who received Propecia saw a net gain in hair count over the study period.

Long-Term Finasteride Results

Some of the participants continued in the study for up to five years. At the two-year mark, 17% of those who received Propecia continued to lose hair, versus 72% in the placebo group. After five years, 100% of those who took a placebo lost more hair, while 35% of the men who took Propecia did.

Clinical Trials of Finasteride for Women

Researchers conducted one clinical trial of finasteride on 137 postmenopausal women who all had androgenic alopecia. The study lasted one year. The results indicated that Propecia was not effective in treating hair loss in postmenopausal women.

Women of childbearing age should not use Propecia or any other finasteride. Furthermore, they should not handle crushed or broken tablets, liquids or topicals containing the drug when they are pregnant. Finasteride can create problems with forming external genitalia in male fetuses, leading to abnormalities at birth.

Are There Differences Between Generic Finasteride and Propecia?

On July 28th, 2006, the FDA approved the first generic form of finasteride. Propecia and generic forms of finasteride contain the same active ingredient, but there are differences in inactive ingredients. Propecia only comes in 1-milligram tablets, while the generic finasteride is available in tablet, liquid and topical forms.

The generic versions are also available in either 1-milligram or 5-milligram doses because they are meant to treat both androgenic alopecia and benign prostatic hyperplasia. If you have a prescription for the treatment of hair loss, you receive a 1-milligram dose. The adverse effects of the generic form of finasteride vs Propecia are the same, as they both contain the same active ingredient.

The biggest difference between generic finasteride and Propecia is the price. While both perform the same function, there is a significant difference in pricing. Brand names are always more expensive than generic forms, and it’s no different with this drug; Propecia carries a higher price tag than what you pay for generic finasteride.

Does Shapiro MD Have Finasteride?

At Shapiro MD, we’re working hard to make hair loss relief easier than ever. With our simple telemedicine platform, we can deliver generic finasteride to your door, if approved, with prescriptions done online by licensed clinicians. It’s fast and easier than ever.

Get started with our free hair quiz right now.