Topical minoxidil therapy for androgenetic alopecia. A 30-month study.

Seventy-two adult male patients were entered into a double-blind, placebo-controlled investigation using 2% to 3% topical minoxidil solution for androgenetic alopecia. Fifty-nine patients completed the initial 12 months, and continued to use 3% topical minoxidil solution in an open study design. Hair regrowth (as measured by hair counts and bald-area diameters) was noted in all treatment groups at four months, and appeared to peak at approximately 12 months. At 30 months, mean hair counts had decreased from the 12-months level, but remained elevated over baseline counts, while mean bald-area diameters returned to baseline. However, 70% of the patients who did continue to use the drug for 30 months had 50% or more hairs than when they originally started the drug therapy. A subset of patients appeared to sustain a continued increase in hair counts after 12 months. No systemic side effects were noted.