THE EFFECT OF CYPROTERONE ACETATE ON THE PLASMA GONADOTROPHIN RESPONSE TO GONADOTROPHIN RELEASING HORMONE

Abstract

Cyproterone acetate (100-150 mg daily) was administered to 8 male patients with excessive libido. Within 3 mo. a significant fall (P < 0.02) in plasma testosterone was demonstrated. The plasma luteinizing hormone (LH) and follicle stimulating hormone (FSH) responses to gonadotropin releasing hormone (LH/FSH-RH) were significantly impaired (P < 0.05). A direct correlation between the resting plasma testosterone level and the LH response to LH/FSH-RH was demonstrated (r = 0.743). The fall in plasma testosterone levels in patients receiving cyproterone acetate may be attributed to suppression of LH release, rather than an antiandrogen effect on the testis or hypothalamus.