Hirsutism results from increased androgen production or excessive androgen activity at the target level. The effect of androgens at the peripheral level depends on the metabolism of testosterone, the ability of free steroid fraction to cross the cell membrane and interaction with intracellular receptors. Pharmacologic treatment focuses on the androgen secretions or the target tissue. Cyproterone acetate has both central and peripheral activity when combined with ethinyl E₂. Flutamide and finasteride are two other agents that have been used in the treatment of hirsutism. Fruzzetti and associates studied the safety and efficacy of each of these therapies to determine the best treatment regimen in patients with hirsutism.

The authors recruited 45 women with hirsutism who had no evidence of a secondary cause and had not received any hormonal therapy for six months. The women were randomly assigned to one of three treatment groups. The first treatment regimen was 25 mg of cyproterone acetate per day for the first 10 days of the menstrual cycle along with 20 μg of ethinyl E₂ daily for 21 days. The second group received 250 mg of flutamide twice a day, and the third group received 5 mg of finasteride per day. One physician evaluated patients' hirsutism before initiating therapy, and liver function studies were performed to identify hormone levels at baseline and months 3, 6 and 12.

All three therapies significantly reduced hirsutism scores during the study with a similar percent decrease in scores among the groups. No significant side effects were reported in any of the groups, and no one dropped out of the study because of side effects.

Cyproterone acetate with ethinyl E₂ has proved to be effective in reducing hirsutism. However, few trials looked at the safety and efficacy of flutamide and finasteride. This study demonstrated that these three agents were equally effective in reducing hirsutism scores, although they have different modes of activity. The authors conclude that all three agents can be used, with minimal side effects, in the treatment of hirsutism.