Finasteride is a FDA approved drug for treating hairloss. It comes in a 1mg pill form and is available by prescription only for men. Finasteride grows hair in about 40-50% of men after two years. The most common side effects are decreased sexual desire or lowered amount of ejaculate in less than 2% of men, although almost as many men who received the placebo experienced this as well.
Finasteride is the generic name for the brand name drugs Proscar and Propecia. Finasteride was originally developed by the pharmaceutical company Merck as a drug (Proscar) to treat enlarged prostate glands.
During the trials on men with prostate problems, researchers noted an intriguing side effect: hair growth. Since finasteride had already been approved by the FDA to treat enlarged prostates in men, Merck decided to pursue the possibility of developing finasteride as the first pill to treat male pattern baldness. Minoxidil, a topical liquid solution, was already on the market.
In December 1997, the FDA approved a 1mg dose of finasteride for the treatment of androgenetic alopecia (male pattern baldness) in men. Propecia is the first drug in history to effectively treat male pattern baldness in the majority of men who use it.
How Finasteride Works
Finasteride’s hair-raising success is due to its ability to specifically inhibit 5-alpha-reductase, the enzyme that converts testosterone into a more potent androgen dihydrotestosterone (DHT).
Propecia’s 1 mg dose of finasteride can effectively lower DHT levels in the scalp by as much as 60% when taken daily. It is DHT that shrinks or miniaturizes the hair follicle, which eventually leads to baldness. This 60% reduction in DHT has proven to stop the progression of hair loss in 86% of men taking the drug during clinical trials. 65% of trial participants had what was considered a substantial increase of hair growth.