antiandrogen
n. a substance that reduces or blocks the physiological effects of androgens, the male sex hormones, on tissues normally responsive to these hormones. Examples include bicalutamide (U.S. trade name: Casodex), finasteride (U.S. trade names: Propecia; Proscar), flutamide (U.S. trade name: Eulexin), and nilutamide (U.S. trade name: Nilandron). They correct the effects of excessive levels of male sex hormones and may be used to control hair loss and prostate cancer in males and to reverse masculine traits (e.g., excessive facial hair) in females. More controversially, antiandrogens have been used in the treatment of repeat sex offenders (see chemical castration). Also called androgen antagonist.