Chemical Castration in Medicine
Chemical castration is normally used in:
► Treatment of Prostate Cancer: Prostate cancer cells normally grow faster in the presence of testosterone. Medical castration reduces testosterone levels, thus keeping the cancerous cells in check. However, the hormonal therapy does not cure the cancer but only shrinks the cancer to some extent. It is used for advanced cases where surgery cannot produce a cure.
Drugs used to bring about chemical castration include:
► Medroxyprogesterone acetate (MPA): MPA is a long-acting injectable progesterone (a female hormone) that is used as a contraceptive in women. In men, it acts as an anti-androgen. The Depo Provera preparation has to be administered every 3 months.
► Cyproterone acetate: Cyproterone acetate is an anti-androgen that is used to bring about chemical castration.
► Luteinizing hormone-releasing hormone (LHRH) antagonists: These drugs bring about a fall in testosterone levels without causing the initial rise. The LHRH antagonist, degarelix, is used in the treatment of advanced prostate cancer as a monthly injection.
► Other drugs like estrogen and ketoconazole may also be used in cases where the above drugs are ineffective. In addition, newer drugs are also being evaluated in the treatment of advanced prostate cancer.