Pituitary function in adult males receiving medroxyprogesterone acetate.

The pituitary, adrenal, and gonadal functions of nine males (six XY, two XYY, and one XY/XYY) were studied after at least 6 months of medroxyprogesterone acetate (MPA) therapy for antisocial or sex-offending behavior. Five were studied both before and during therapy, four only during therapy. MPA was effective in decreasing serum gonadotropin and plasma testosterone concentrations. MPA caused no change in the 24-hour rhythm or total integrated concentration of growth hormone. The plasma cortisol circadian rhythm was suppressed but not obliterated by MPA therapy. Although a significant decrease (P less than 0.001) in 24-hour integrated concentrations of plasma cortisol was also found, the rise in the plasma cortisol level after insulin-induced hypoglycemia was unchanged.