OBJECTIVE: To investigate the effects of low dose flutamide (250 mg/d) on hirsutism score and hormone levels in women with hirsutism. DESIGN: Nonrandomized, prospective clinical trial. PATIENTS: Forty-one patients with moderate-severe hirsutism were included in the study. INTERVENTION: Hirsute patients received 250 mg/d flutamide for a period of 6 months. MAIN OUTCOME MEASURES: Hirsutism score, FSH, LH, E2, total T, free T, androstenedione, DHEAS, PRL, 17-hydroxyprogesterone, and sex hormone-binding globulin levels were detected in all the patients before treatment and every 3 months during treatment. RESULTS: Treatment with the antiandrogen flutamide resulted in a particularly rapid and marked decrease in the hirsutism score, which decreased from 17.48 +/- 5.35 to 5.07 +/- 2.89 after 6 months. No significant changes in the levels of hormone and no serious side effects were observed in the study. CONCLUSION: The low-dose flutamide, 250 mg/d, is a cost-effective drug in the treatment of hirsutism. Low-dose flutamide may be used in place of high-dose flutamide, 500 to 750 mg/d.