Cyproterone acetate for hirsutism

Hirsutism is a distressing and relatively common endocrine problem in women which may prove difficult to manage. Cyproterone acetate, an anti-androgen, is frequently used to treat hirsutism, usually in combination with ethinyl estradiol.

The objective of this review was to investigate the effectiveness of cyproterone acetate alone, or in combination with ethinyl estradiol, in reducing hair growth in women with hirsutism secondary to ovarian hyperandrogenism.

The Cochrane Menstrual Disorders and Subfertility Group trials register was searched (last search - 4 June 2002). The Cochrane Menstrual Disorders and Subfertility Group register is based on regular searches of MEDLINE (1966 to 2002), EMBASE (1980 to 2002), CINAHL (1982 to 2002), PsycINFO (1987 to 2002) and CENTRAL (Issue 2, 2002 of the Cochrane Library) the handsearching of several journals and conference proceedings, and searches of several key grey literature sources. All publications of randomised controlled trials of cyproterone acetate with or without estrogen versus placebo or other drug therapies for hirsutism were identified.

All randomised controlled studies comparing:- cyproterone acetate to placebo- cyproterone acetate with ethinyl estradiol to placebo- cyproterone acetate with ethinyl estradiol to cyproterone acetate alone- cyproterone acetate (with or without estradiol) to other medical therapies for treatment of hirsutism.

Eleven studies were identified which fulfilled the inclusion criteria. Nine randomised studies were included in the review, and two were excluded because of insufficient information. Only one study had more than 100 women included in the analysis. The major outcomes included: subjective improvement in hirsutism, changes in Ferriman Gallwey scores, changes in linear hair growth and hair shaft diameter, alterations in endocrine parameters, side effects to treatment, withdrawals during therapy

There were no clinical trials comparing cyproterone acetate alone with placebo. There was one small study comparing cyproterone acetate in combination with ethinyl estradiol to placebo. In this study there was a significant subjective reduction in hair growth with cyproterone acetate therapy, although the confidence limits were large. There were no studies comparing cyproterone acetate alone with cyproterone acetate in combination with ethinyl estradiol to treat hirsutism. In studies where cyproterone acetate was compared to other drug modalities (ketoconazole, spironolactone, flutamide, finasteride, GnRH analogues) no difference in clinical outcome was noted. There were, however, endocrinological differences in androgen and estrogen levels between different drug therapies. There were insufficient data to assess differences in side effects between women treated with cyproterone acetate and other medical therapy.

Cyproterone acetate combined with estradiol results in a subjective improvement in hirsutism compared to placebo. Clinical differences in outcome between cyproterone acetate and other medical therapies were not demonstrated in the studies included in this review. This may be because of the small size of the studies, lack of standardized assessment and lack of objective determinants of improvement in hirsutism. The endocrinological effects of the different drug therapies reflect the mode of action. Larger carefully designed studies are needed to compare efficacy and safety profiles between drug therapies for hirsutism.