Lack of effect of spironolactone on hair shaft diameter in hirsute females

Because of its anti-androgenic activity spironolactone 50-200 mg daily is advocated widely for the management of female hirsutism but this practice lacks adequately controlled experimental support. In a double-blind placebo controlled study of the efficacy of spironolactone 100 mg daily in idiopathic hirsutism we were unable to demonstrate objective benefit from spironolactone treatment. The mean effect of spironolactone given over a 9 month period was to increase hair shaft diameter by +15% with 95% CI (-0.4% to +29%). In addition there were no changes in circulating serum androgen concentrations.