One-Year Follow-Up of Serum Prolactin Level in Schizophrenia Patients Treated with Blonanserin: A Case Series

In our previous study, a prolactin elevation was more frequently in risperidone than in blonanserin; however, it was more often in blonanserin than in olanzapine. Therefore, while a rate of PRL rising is low to moderate, hyperprolactinemia is a considerable adverse effect in the blonanserin treatment. In this study, to examine detailed characteristics of hyperprolactinemia of blonanserin, we analyzed the prolactin data in six schizophrenic patients who were switched to blonanserin from other antipsychotics and followed for one year. As a result, blonanserin dose was clearly associated with serum prolactin level. The average prolactin level was almost normal when the mean blonanserin dosage was 8.0 mg/day. Regardless of the dose decrease of blonanserin, there were no remarkable changes in symptoms and social functions. Based on our findings, we conclude that low dose blonanserin medication may be useful for schizophrenia maintenance treatment without hyperprolactinemia and a high rate of relapse.