Cyproterone acetate for severe hirsutism: results of a double-blind dose-ranging study

The objective was to determine if cyproterone acetate (CPA) therapy for hirsute women demonstrated a dose response.

A double-blind dose-ranging study of the effect of 3 doses of cyproterone acetate for a period of 12 months.

Twenty-one hirsute women received the Dianette contraceptive pill (35 micrograms ethinyl oestradiol + 2 mg CPA, Schering Healthcare, UK), 20 received Dianette plus 20 mg CPA and 19 received Dianette plus 100 mg CPA: supplementary CPA was administered on days 1-10 of the birth control pill cycle as described by Hammerstein.

Hair growth was measured using the clinical scale of Ferriman and Gallwey and by direct measurement of hair shaft diameter and linear growth of hair on the face, forearm, abdomen and thigh.

Thirty-eight women completed 12 months therapy, eight withdrew due to side-effects and 14 were lost to follow-up. All three dose schedules produced significant reductions in clinical hair growth scores. This reduction was seen after 6 months with Dianette alone (P less than 0.005) and after 3 months with both the higher doses (P less than 0.01). There were no significant differences between the effect of different doses at any of the three-monthly time points. Hair diameter measurements were reduced by all doses after 12 months: face by 27*, 37, 37%*, forearm 5, 10, 8%*, abdomen 22*, 39*, 33%*, thigh 12, 24*, 30%* (median reductions (*P less than 0.01) for Dianette, D + 20 mg CPA and D + 100 mg CPA respectively). There were no significant reductions in daily linear growth rates. A comparison of the percentage reduction in hair shaft diameter at each site demonstrated no significant difference between doses, although the reductions by the three doses on the forearm, abdomen and thigh suggested a trend towards a dose response.

We conclude that cyproterone acetate 2 mg daily appears to be as effective as higher doses in the therapy of hirsute women.