Hirsutism is a common clinical problem for which a pharmacologic approach is often preferred to mechanical hair removal. The goal of drug treatment is to suppress the production or action of androgen. Contraceptives are widely used but are of limited value in women with established hirsutism. Gonadotropin-releasing hormone analogs have been shown to be of some benefit, but antiandrogen drugs, often given along with nonandrogenic oral contraceptives, are the most reliable. Spironolactone and cyproterone acetate are the most commonly used agents, but they are associated with frequent menstrual irregularity. Other antiandrogens have been proposed for use with hirsutism, including flutamide, a pure antiandrogen that acts at the androgen receptor site, and finasteride, a potent competitive inhibitor of an enzyme that converts testosterone to the active metabolite dihydrotestosterone. Moghetti and associates compared the clinical efficacy of spironolactone, flutamide and finasteride in a double-blind, placebo-controlled trial of hirsute women.

Forty young women with moderate to severe hirsutism were enrolled in the study. Hair growth was estimated by using a standardized scoring system measuring shaft diameters of hair plucked from the linea alba. Patients were randomized to double-blinded treatments once daily for six months with one of the following: spironolactone (100 mg), flutamide (250 mg), finasteride (5 mg) or placebo. Hirsutism and hormonal parameters were evaluated in each patient at baseline and at the end of the study.

All three drugs appeared to be equally effective in decreasing hair diameter and improving standardized hirsutism scores. Similar improvements were found in women with polycystic ovary syndrome and women with nonovarian hyperandrogenism. Transient metrorrhagia was reported in five women taking spironolactone. Flutamide was not associated with liver toxicity in this study, although this association has been noted in other studies. Finasteride was not associated with any appreciable side effects.

The authors conclude that all three medications were effective in the treatment of hirsutism, but that finasteride appears to be the current best choice because of its lack of side effects. All antiandrogens must be avoided during pregnancy to prevent feminization of a male fetus. Further research may be useful to evaluate the synergistic effects of combined therapies.

editor's note: Early management of hirsutism is preferred because long-standing facial hair responds more slowly to therapy. Drug therapy requires six to 18 months for maximal results. Progress can be measured by evaluating the time between hair removal efforts (i.e., the interval between episodes of “plucking” or electrolysis) for satisfactory cosmesis.

Current medical treatments include ovarian suppression with oral contraceptives or gonadotropin-releasing hormone analogs. Antiandrogens that inhibit the binding of testosterone and dihydrotestosterone to the androgen receptor, including spironolactone, cyproterone acetate and flutamide can be used, although flutamide has been associated with severe hepatic adverse effects. The 5-alpha-reductase inhibitors, such as finasteride, are also useful, but should be avoided in pregnancy. Optimal therapy probably includes mechanical hair removal combined with judicious use of medications. Unfortunately, once antiandrogen therapy is initiated, it must be continued, because cessation is often followed by recurrence of hair growth.—r.s.