Cyprostat, known generically as cyproterone acetate, is a medication primarily used in the treatment of advanced prostate cancer. It belongs to a class of drugs known as anti-androgens, which work by blocking the action of male hormones (androgens) in the body, thereby slowing the growth of cancer cells. Cyprostat is also used in the management of other conditions related to androgen excess, including severe acne, excessive hair growth in women (hirsutism), and is part of hormone therapy for transgender women. It is available in tablet form and is usually taken once daily or as directed by a healthcare provider. Cyprostat can cause a range of side effects, and its use should be closely monitored by a healthcare professional.