Thirty one women with hyperandrogenism, clinically divided into polycystic ovary syndrome (PCOS)--28 women and idiopathic hirsutism (I.H.)--3 women, were treated with low dose spironolactone (50 mg or 75 mg daily) for average five months. There was an excellent clinical response in 19 (61%), incomplete response in 8 (26%), no response in 5 women. Six of 18 patients with sterility became pregnant during the one year after treatment and delivered a healthy infant at term. Two patients dropped out of the trial because of intolerance of the therapy. Remarkable change of the menstrual pattern characterised as polymenorrhea was major side effect of the therapy. Other side effects were not problem. Spironolactone caused statistically significant reduction in testosterone, luteinizing hormone and prolactin values at the end of the treatment. Our results demonstrate that low-dose spironolactone is effective in the treatment of hyperandrogenism in women.