Anti-androgens in gynaecological practice.

Hirsutism and acne in women are common distressing problems. Unwanted hair growth, acne and seborrhoea result from the action of androgens on the skin. Such effects depend not only on increased androgen production by the ovary or adrenal gland but also on the bioavailability of androgen to peripheral tissues. This in turn is related to transport of androgens in plasma by specific binding proteins and to peripheral metabolism of testosterone and androstenedione to their more potent 5 alpha-reduced derivatives. An effective anti-androgen is one which blocks the androgen receptor-mediated actions of testosterone and DHT on skin. CPA, the treatment of choice in the UK, is a potent androgen receptor-blocking steroid which also has progestational properties. When combined with ethinyloestradiol it also suppresses ovarian function, thus reducing androgen production, and provides effective contraception.