Growth hormone (GH), and prolactin (PRL) responses to the administration of growth hormone-releasing hormone (GHRH) (1 μg/kg) were evaluated in a group of 18 drug-free, acute, young male schizophrenics and in a group of age-matched normal controls. Cortisol responses were also evaluated. No difference in mean plasma GH, PRL and cortisol plasma basal values or in GH and PRL responses to GHRH between schizophrenics and controls was observed. Our failure to demonstrate a difference in GH response to GHRH between schizophrenics and controls would seem to indicate that GH secretory pituitary reserve is intact in young acute male schizophrenics. Cortisol values did discriminate between schizophrenics and controls (p< 0.05). In our sample, both schizophrenics and normal controls showed a slight but significant (p < 0.03) and transitory increase in plasma PRL response to GHRH