Use of cyproterone acetate (CPA) in the treatment of acne, hirsutism and virilism

Abstract

Cyproterone acetate, being both an antiandrogen and a progestogen, must be administered in women together with an oral estrogen in a “reverse sequential regime” to ensure cyclic withdrawal bleedings and to preclude conception. Such a regime consisting of the oral intake of 100 mg cyproterone acetate from day 5 to 14 and 50μg ethinyl estradiol from day 5 to 25 of the cycle has been applied to over 600 patients, at 5 German centres, of whom about one third have been under the care of the author's group. Acne and seborrhoea are the symptoms which respond first and best with an almost 100% success rate after 3 months of medication. Usually, 6–9 months are necessary to improve hirsutism or even make it disappear in 60 to 80% of the subjects. The rest of the patients failed to respond or showed only poor improvement. Alopecia due to androgen overproduction was reduced only in about 50% of the individuals after a one-year treatment period. Following termination of the medication, the various symptoms of virilism reappeared more or less quickly and markedly in the majority of the patients unless they are placed on oral contraceptives containing a derivative of 17-acetoxyprogesterone. Side effects are comparable to those observed in oral contraception except for tiredness, lassitude and loss of libido which are seen more often. On the basis of hormonal analyses in blood and urine, it is suggested that the newly developed treatment acts both by competition with the androgens at the receptor sites and by lowering the ovarian androgen biosynthesis. Also, ovulation is reliably suppressed.