Spironolactone (100 mg) for 25 days in each menstrual cycle was assessed over 6 months for treatment of hirsutism in 35 patients. Five patients withdrew due to either nausea or polymenorrhea. the latter problem was encountered in 16 patients. of the 30 remaining patients, 17 had a significant reduction in hair growth as assessed by Ferriman and Gallwey hair scores (p<0.05). the only significant change in endocrine parameters was a reduction in serum testosterone (p<0.05). Treatment with spironolactone alone was inferior to our previous experience with the cyproterone acetate–estrogen combination.