Basal and stimulated (0.2 mg TRH, 0.025 mg LHRH) levels of prolactin, TSH and LH were measured in serum of 12 male and 10 female chronic schizophrenic patients, hospitalized and treated with neuroleptics from 6-21 years. The mean values of the 3 pituitary hormones were within the normal range in both sexes. Tolerance to the prolactin increasing effect of neuroleptics appears to develop after long-term neuroleptic treatment. TSH and LH secretion are not markedly impaired by chronic neuroleptic treatment.
