Effect of finasteride in idiopathic hirsutism

Increased 5α-reductase activity has been found in hair follicles of hirsute women, suggesting a pathogenetic role. The aim of the present study was to evaluate the effect of finasteride in the treatment of idiopathic hirsutism. Twenty-seven women with idiopathic hirsutism, aged 16–35 years, were treated for 6 months with finasteride, 5 mg once daily. Fourteen patients were on finasteride alone (group A), while the remaining received in addition an oral contraceptive (group B). Clinical, hormonal and biochemical evaluation were performed before, and after 3 and 6 months of treatment. Clinical evaluation was repeated 6 months after drug discontinuation in seven patients. Treatment was well tolerated by all patients; no side effects or adverse reactions were reported. A significant improvement of hirsutism was obtained by finasteride; clinical score observed at the 6th month of therapy was reduced from 11.71 ±2.23 to 7.92±1.81 (p<0.05) and from 14.92±6.13 to 9.3±2.75 (p<0.05) in group A and B, respectively. Clinical score in seven patients was still 8.61 ±2.28 (p<0.05) 6 months after the end of therapy. Finasteride treatment alone (group A) induced a slight increase, though not significant, in serum androgens; DHT and SHBG did not change. In group B (finasteride plus oral contraceptive) total testosterone and free testosterone showed no significant decrease; after 6 months of therapy DHT was reduced significantly, while SHBG levels were increased. These data demonstrate that 5α-reductase inhibition may be an effective treatment in women suffering from idiopathic hirsutism. This approach may be attractive due to the absence of adverse reactions, although the necessity of an adequate contraception should be kept in mind.