As prolactin secretion from the pituitary is negatively regulated by dopamine signaling from the hypothalamus [87], the main focus on prolactin in clinical settings with regard to psychiatric disorders has been antipsychotic induced hyperprolactinemia, an adverse effect caused by the administration of common antipsychotics which target dopamine D2 receptors [88]. This evidence concerns the gene DRD2 and hyperprolactinemia.