Prolactin levels in schizophrenic patients receiving perospirone in comparison to risperidone.

Serum prolactin levels were investigated in 41 patients with schizophrenia who were receiving clinically effective doses of perospirone or risperidone for more than 4 weeks. In order to determine baseline prolactin levels, blood samples were obtained in the morning, 10 - 14 h after antipsychotic medication. Median levels were within normal limits in both female and male patients receiving perospirone, while risperidone induced significant elevation. These results suggest that in contrast to risperidone, where baseline prolactin levels were elevated 5.3-fold in female and 4.2-fold in male patients, baseline prolactin levels are not elevated after treatment with perospirone. However, these results should be cautiously interpreted, because drug-by-time interaction has previously been reported in antipsychotic-induced hyperprolactinemia.