Melperone, an atypical antipsychotic drug with clozapine-like effect on plasma prolactin: Contrast with typical neuroleptics

Objective: To evaluate the effect of melperone, a butyrophenone with atypical antipsychotic properties, on plasma prolactin (PRL) concentrations compared with clozapine and typical neuroleptics. Methods: Analysis of pre- and post-treatment PRL levels collected prospectively per protocol in a non-randomized study of 26 melperone-, 76 clozapine-, and 66 neuroleptic-treated patients with schizophrenia or schizoaffective disorder. Cross-sectional analysis of a larger sample of patients with PRL data was also performed. Results: For males, post-treatment PRL levels were significantly higher in the typical neuroleptic group compared with the melperone (p=0.0001) and clozapine (p=0.0001) groups, with no significant difference between clozapine and melperone. For females, post-treatment PRL levels were significantly higher in the melperone group as compared to the clozapine group (p=0.004). There were too few typical neuroleptic-treated females to permit analysis of this sample. However, the cross-sectional analysis of PRL data confirmed the results for melperone- and clozapine-treated females, and showed higher PRL levels in typical neuroleptic-treated females as compared with those who received melperone and clozapine. Conclusion: Melperone did not significantly increase PRL levels in male patients. However, melperone and typical neuroleptics caused increase in PRL levels in females. Further study of melperone's effects on PRL concentration is warranted.