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Home » Drug Information » Recently Approved Drugs » 1997
Medical Areas: Dermatology/Plastic Surgery

Drug Information

The following information is obtained from various newswires, published medical journal articles, and medical conference presentations.

Drug Name: Propecia

Company: Merck
Approval Status: Approved December 1997
Treatment Area: male baldness

General Information

Propecia (finasteride) has been approved for the treatment of male pattern baldness. Propecia is the first drug available in pill form.

Clinical Results

In men with mild to moderate hair loss, clinical trials showed that 83% of the male patients had kept their hair or grown more after one year of treatment.

Side Effects

Side effects reported in approximately 2% of patients included a diminished desire for sex, difficulty achieving an erection, and/or a decreased amount of semen. The drug will not be marketed for women because safety and effectiveness have not bee established in women, and it is associated with birth defects.

Mechanism of Action

The drug's active ingredient, finasteride, is already approved for the treatment of prostate enlargement. It works by blocking an enzyme called 5-alpha reductase, which is responsible for the formation of dihydro-testosterone in a man's body. The enzyme converts testosterone to DHT, and it is believed that DHT is a key factor in male pattern hair loss. Finasteride decreases the concentration of DHT in a man's scalp by about two-thirds.


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