Cyproterone Acetate

Cyproterone acetate: what it does

Picture the receptors on an oil gland or a hair follicle as locks that androgens open. Cyproterone acetate is a synthetic progestogen that fits those locks and stays put, so the androgens find them taken. Oil glands quieten and hair growth slows. In the pill it works with ethinylestradiol, an oestrogen that lowers the body's own androgen output and keeps the cycle regular. Searches for this ingredient mostly end with women whose acne or unwanted hair is driven by androgens.

On PockDose it is sold only in that combination. Plain cyproterone tablets exist, but at far higher strengths and for other purposes such as prostate cancer treatment, and they are a separate medicine from the low-dose pills here.

The two listings

Both products are 2/0.035mg tablets, each holding 2mg of cyproterone acetate and 0.035mg of ethinylestradiol:

• Cyproterone Acetate And Ethinylestradiol is the combination under its ingredient names, listed for severe acne and hirsutism (excess hair in a male-type pattern).
• Diane 35 is the branded name for the same pair, listed for acne and hirsutism.

Nothing separates them on strength or form, so choose by the pack sizes and prices each page shows.

Who it suits, and who should skip it

Creams and antibiotics sometimes fail, and that is when most women reach for this combination. It treats acne or hirsutism in women who are not pregnant. It stops ovulation too, so it behaves as a contraceptive pill and takes the place of one rather than joining it. Breastfeeding, a history of clots, stroke or heart attack, migraine with aura, severe liver disease, hormone-dependent cancers, unexplained vaginal bleeding, uncontrolled high blood pressure and diabetes with blood vessel damage all rule it out. Higher-dose cyproterone has been linked to meningioma, and although low-dose combinations like these did not show that risk, anyone who has had a meningioma avoids them.

Medicines that change how it works

Enzyme-inducing medicines speed up how the liver clears the hormones and can cause breakthrough bleeding or weaker protection. The best known are rifampicin, phenytoin, carbamazepine, phenobarbital and the herbal remedy St John's wort. Some HIV medicines act the same way. Common side effects are nausea, headache, breast tenderness, mood changes and weight gain, and clots are the serious risk, especially for smokers.