Is Second-Generation Antipsychotic-Induced Hyperprolactinemia Due to Biologically Active Prolactin or to Biologically Inactive Macroprolactin? Results From a Prospective Study

Letter to the Editor

Sir: Hyperprolactinemia is of particular concern with antipsychoticmedication, as symptoms associated with high prolactinlevels, e.g., sexual dysfunction, can have a negativeimpact on the patient’s adherence to treatment, and has significantimplications for the short-term and long-term health ofpatients. In general, second-generation antipsychotics (SGAs)produce lower increases in prolactin levels than first-generationantipsychotics due to the differences in these drugs’ binding affinityfor the dopamine D2 receptor. Particularly, olanzapine,quetiapine, and clozapine have been shown to produce no significantor sustained increase in prolactin. Conversely, SGAsthat have been associated with increases in prolactin levels areamisulpride, zotepine, and risperidone.