PROLACTIN RESPONSE TO BROMPERIDOL TREATMENT IN SCHIZOPHRENIC-PATIENTS

The prolactin response to an antipsychotic drug, bromperidol was studi ed in 24 schizophrenic in-patients (13 males, 11 females). Eight patie nts were given 6 mg/day, 8 were given 12 mg/day and 8 were given 18 mg /day. Duration of treatment was 3 weeks. Plasma concentrations of brom peridol and reduced bromperidol were measured by high-performance liqu id chromatography, and that of prolactin was measured by radioimmunoas say. Bromperidol treatment significantly (P<0.01) increased plasma con centration of prolactin each week. The mean+/-S.D. of the Delta-prolac tin (the mean concentration during treatment minus the pretreatment co ncentration) was 13.3+/-12.4 ng/ml. Multiple regression analysis showe d that the Delta-prolactin concentration was significantly greater in females than in males (P<0.05) and correlated to plasma concentrations of bromperidol (P<0.001) and reduced bromperidol (P<0.0001). These re sults suggest that the prolactin response to bromperidol treatment dep end on plasma concentrations of both bromperidol and reduced bromperid ol and gender, and that reduced bromperidol is involved in the pharmac ological effects during bromperidol treatment.