Topical minoxidil for androgenetic alopecia: optimizing the chance for success by appropriate patient selection.

Cosmetically acceptable hair growth was achieved in 18 (32%) of 56 balding male subjects during a 12-month study using 2 or 3% topical minoxidil. The criteria for successful hair regrowth devised from those subjects were: (1) no baldness greater than a Hamilton pattern IV; (2) a balding vertex area smaller than 10 cm in diameter, and (3) a balding process of less than 5 years' duration. Frontotemporal hair loss did not respond to treatment and in fact progressed in severity, despite the twice-daily applications of minoxidil. In a subsequent study of 91 subjects who met these three criteria, 51 (56%) subjects achieved cosmetically acceptable hair growth after 1 year using 2% topical minoxidil (Regaine; registered trade mark of The Upjohn Company) twice daily.