Finasteride in the treatment of hirsutism: new therapeutic perspectives.

OBJECTIVE: To determine of the clinical and hormonal effects of finasteride (Proscar; Merck, Sharp, and Dohme, Rahway, NJ) in the treatment of idiopathic hirsutism and hirsutism in patients with polycystic ovary syndrome (PCOS). DESIGN: Controlled clinical study. SETTING: Istitute of Obstetrics and Gynecology, University of Naples "Federico II." PATIENTS: Ten women affected by idiopathic hirsutism and 15 women with PCOS. INTERVENTIONS: Finasteride was administered orally at a daily dose of 5 mg for a period of 6 months. MAIN OUTCOME MEASURES: Rating of hirsutism with the Ferriman-Gallwey method; serum androgen assays. RESULTS: Finasteride produced a reduction in the average hirsutism scores ( > 50% in all patients), whereas no change was observed in serum T, androstenedione, and DHEAS levels. A significant reduction was measured in serum dihydrotestosterone and 3 alpha, 17 beta-androstenediol glucuronide levels. CONCLUSIONS: This study demonstrates that symptomatic hirsutism has to be considered as a skin disease associated with the increased activity of the 5 alpha-reductase. It also indicates that the selective 5 alpha-reductase inhibitor, finasteride, is very effective and well tolerated in the treatment of both idiopathic hirsutism and of hirsutism in patients with PCOS.