PROLACTIN RESPONSE TO NEMONAPRIDE, A NEW ANTIPSYCHOTIC DRUG, IN SCHIZOPHRENIC-PATIENTS

The prolactin response to nemonapride, a new antipsychotic drug, was s tudied in 27 schizophrenic inpatients (12 males, 15 females). The dail y dose of nemonapride was 18 mg/day, and the duration of treatment was 3 weeks. Plasma prolactin concentrations were measured by enzyme immu noassay. Nemonapride treatment significantly (p < 0.01) increased prol actin concentrations at each week in both genders. The Delta prolactin (the mean concentration during 3 weeks minus the pretreatment concent ration) was significantly (p < 0.01) greater in females (mean +/- SD, 81.6 +/- 57.8 ng/ml) than males (34.9 +/- 19.8 ng/ml). The present stu dy thus shows that nemonapride treatment markedly increases prolactin concentrations in schizophrenic patients, with greater responses in fe males than males, suggesting a strong D2 receptor blockade property of the drug. (C) 1997 John Wiley & Sons, Ltd.