Cyproterone for hirsutism

Cyproterone is used in hirsutism for its antiandrogen action. It also has a pronounced progestogenic effect and suppresses ovarian androgen production. However, cyproterone also interacts with glucocorticoid receptors, which may explain weight gain seen with high doses.

If used alone, cyproterone usually leads to oligomenorrhoea or amenorrhoea and hypoestrogenism. Therefore, it should be used together with a COC in premenopausal or perimenopausal individuals. Use of cyproterone is generally not recommended in postmenopausal individuals because low-dose formulations are not available; doses available to treat hirsutism may be associated with increased risk of breast cancer and cardiovascular disease in postmenopausal individuals.

Cyproterone is usually given for the first 10 days of each COC cycle. This permits the effect of cyproterone to wear off before the hormone-free interval of the COC cycle if an individual wishes to have a withdrawal bleed. The withdrawal bleed may be delayed because of the long half-life of cyproterone. If it is delayed for more than 1 week, a pregnancy test should be considered.

For females who are premenopausal or perimenopausal, use:

cyproterone 50 mg orally, once daily for 10 days per month, starting on the first day of the cycle of a combined oral contraceptive (see Formulations of combined hormonal contraception available in Australia for formulations). If response is inadequate after 3 months, increase to 100 mg daily. Once maximal effect is achieved, consider reducing or stopping cyproterone. hirsutism cyproterone    

Adverse effects of cyproterone include fatigue, weight gain, breast tenderness and reduced libido.

Prolonged use of 40 mg to 200 mg daily of cyproterone has been associated with the development of meningiomata. A causal link has not been proven, but tumour shrinkage has been reported in some cases after stopping the drug. Current guidelines do not advocate routine monitoring for meningiomata. However, once maximal effect is achieved, consider reducing or stopping cyproterone because of the possibility of increased meningioma risk.