Finasteride (Proscar, Propecia) is an antiandrogen, prescription drug that is used to treat male-pattern hair loss (androgenic alopecia) and an enlarged prostate (benign prostatic hyperplasia) by blocking the conversion of testosterone into dihydrotestosterone (DHT). Finasteride can reduce the rate of hair loss and stimulate regrowth. It may also be prescribed to prevent prostate cancer. In females, finasteride can be used to treat excessive hair growth, such as facial hirsutism. In transgender females, it can be prescribed to combat the hair loss effects of hormone replacement therapy.
Proscar and Propecia are the established branded versions of Finasteride, both produced by Merck & Co., but various generic versions are widely available. The chief difference between Proscar and Propecia are different dosages (5mg vs. 1mg per tablet). Both are taken orally.
Depending on its use, and the severity of the targeted condition, the prescrbed dose of finasteride and treatment duration may vary.
It is best to follow your doctor’s guidance on when and how to take Finasteride.
Finasteride is generally safe, but patients may experience some or all of the following mild side effects:
More severe side effects of Finasteride are rare, but for a small percentage of patients there can be sexual side effects during treatment and for several months after treatment has stopped. Seek medical advice in case you notice any of the following symptoms:
Several long-term studies of both Proscar and Propecia of up to seven years indicate that Finasteride is generally well tolerated, with the single most common side effects being temporary erectile dysfunction and loss of sexual interest. However, only some men are affected in this way and research shows that if these effects occur, they tend to be most severe during the initial phase of treatment, and then gradually decrease in intesity. Moreover, two to four months after the medication is discontinued, in almost all affected patients , sexual side effects fully resolve.
Finasteride treatment can be stopped at any time and at the earliest sign of sexual side effects. Although Finasteride has a long and proven track record of reversing male-pattern hair loss, it is recommended that you speak to your doctor to find out whether Finasteride is the right drug for you.
Long-term use of finasteride may raise the risk of rare aggressive forms of prostate cancer. But the evidence is conflicting. One landmark long-term study (1993-2000) by the U.S. National Cancer Institute (NCI) with nearly 20,000 men showed Finasteride significantly decreased the risk of prostate cancer by 25%, but at the same time could raise the risk of rare aggressive cancer types. However, recent research which followed up on the participants of the original NCI study and was published in 2019 could not find any notable difference in prostate cancer mortality between the Finasteride and the placebo groups. Further clinical trials are needed before a final conclusion can be reached on whether Finasteride indeed raises the risks of rare aggressive prostate cancers.
For adults taking finasteride, there is no risk of overdose. Finasteride was studied in one-off doses of up to 400 mg and in continuous doses of up to 80 mg per day for three months. No significant adverse effects beyond the above-mentioned side effects were observed.
Finasteride may cause birth defects in newborns. Pregnant women are thus advised by the FDA to not take Finasteride a few months prior, and for the entire duration of the pregnancy.
If you have chronic liver disease, dyou should not take Finasteride.
Though there are no known major interactions with other drugs, consult your doctor before using finasteride.