We evaluated the efficacy of long-term cimetidine in treating hirsutism by monitoring four indices: subjective hair removal practice, grading of hair growth by the Lorenzo scale, photography, and hair weight measurement. Of 20 women with moderate to severe facial hirsutism treated with cimetidine, 300 mg four times daily, nine were followed for 48 weeks or longer. Of these nine subjects who completed 48-72 weeks of treatment, only two showed a decrease in hirsutism. None of the 11 subjects treated for less than 48 weeks had any decrease in hirsutism. We conclude that cimetidine, a weak antiandrogen, is not sufficiently effective to use in the treatment of hirsutism.