Plasma concentrations of remoxipride and haloperidol in relation to prolactin and short-term therapeutic outcome in schizophrenic patients.

Plasma concentrations of remoxipride and haloperidol as well as prolactin (PRL) were determined in 20 patients with acute symptoms of schizophrenia. Ten patients received remoxipride and ten patients haloperidol for a period of 6 weeks. A significant linear correlation was found between the plasma level of remoxipride and the dosage applied (P less than 0.02) as well as between the corresponding haloperidol dosage and plasma concentration (P less than 0.05). In both patient groups a significant reduction in psychopathology was observed during the trial period (P less than 0.001). In the haloperidol group this was associated with a clearcut elevation of plasma PRL, whereas in the remoxipride group after an initial rise for 4 weeks, the mean PRL level returned to baseline at the end of the study.