Minoxidil and Finasteride

Minoxidil (brand name Rogaine, now OTC) dilates blood vessels and was originally developed as an oral medication to treat high blood pressure. This lotion promotes hair growth in about 25% of men and women, though it may take several months to work. New hair is usually thinner and lighter, like baby hair, and grows mostly on the top of the head, not at the hairline. Its effects may fade with time. Skin irritation is the most commonly reported side effect. Dizziness and increased heart rate have also been reported, but rarely.

Finasteride (brand name Propecia) is the same oral prescription drug used in higher doses (and called Proscar) to treat an enlarged prostate. It inhibits the conversion of testosterone to DHT. Propecia is not effective in men who are completely bald, but it does promote hair growth and slow hair loss in men who are just beginning to lose hair. In one study 60% of men had new hair growth and more than 80% slowed their hair loss after 6 to 12 months of treatment.

From UC Berkeley Wellness Letter