A 3% topical minoxidil solution was used to treat 31 normotensive persons (13 male, 18 female) with extensive alopecia areata. After 15 months, three patients (14%) had 75%-100% regrowth, 13 (59%) had some form of regrowth, and nine (41%) had no regrowth. In the initial three-month double-blind portion of the study, minoxidil was not shown to be more effective than placebo. Biopsy specimens from eight patients who underwent biopsy prior to treatment, after three months, and posttreatment showed no significant change in peribulbar or perivascular inflammation. Prominent, new anagen follicles were observed. The 3% topical minoxidil was generally well tolerated and skin irritation was minimal. Blood pressure monitoring revealed no significant changes in diastolic or systolic pressures. Minoxidil is a relatively safe treatment for extensive alopecia areata and may be effective in the treatment of some cases of recalcitrant disease.