dopamine, prolactin and treatment of psychoses

Prolactin (pro-lactis, lat.) is a hormone discovered around eight decades ago, with a numerous functions in human body including the effects on growth and development, influences on behavior, metabolism, reproduction, etc. More than 60 years after antipsychotic drugs were introduced, these medications have been keeping prolactin in the spotlight of the psychiatric research community as practically all D2-antagonists change prolactin levels. Hyperprolactinemia has been evaluated in several aspects, either related to patient's characteristics (genetic and functional individual features) or to some drug-related phenomena (penetrability across the blood-brain barrier; D2 receptor binding affinity; capacity to antagonize serotonin receptors), but a critical review of the current literature indicates many unknowns in the field. The present paper will discuss the mechanism and dynamics of changes in prolactin levels throughout treatment with dopamine antagonists on the molecular and clinical level, and the risk of certain acute vs. late adverse effects. Moreover, different techniques that could be applied in common psychiatric practice aiming to control prolactin levels will be considered, with a special emphasis on the possibilities following synthesis and increasing availability of a third generation antipsychotics.