Recent clinical aspects of hyperprolactinemia induced by antipsychotics

This review will address the current understanding of the relationship between hyperprolactinemia and antipsychotic drugs. Hyperprolactinemia is a frequent but often neglected side effect of typical, but also of many atypical antipsychotics. Release of PRL from lactotrope cells is influenced by several factors, such as stress, physical and sexual activity and food assumption. PRL secretion is regulated by hypothalamic-pituitary portal system and its homeostasis is the result of a complex balance between stimulating and inhibitory factors, both endogeneous and esogeneous. The main physiological control mechanism of secretion is played by the inhibitory action of dopamine. Conversely, among stimulation factors, serotonin is probably the main modulator of PRL release. An high number of drugs may cause PRL increase too, such as drugs that reduce dopaminergic functions at SNC level, or drugs with an antagonistic action towards dopaminergic receptors and those increasing serotonergic neurotransmission. Hyperprolactinemia is one of the most frequent endocrine pathologies of the hypothalamic-pituitary axis. Antipsychotics (AP) are the most common cause of druginduced hyperprolactinemia. Not all AP have the same impact on inducing hyperprolactinemia. In this review we will focus on the subdivision of AP in 'PRL-raising' (stimulators) and 'PRL-sparing' (sparers) and on their differences in inducing hyperprolactinemia. Finally we evaluated different complications in patients with antipsychotics induced hyperprolactinemia that may cause not only short-term side effects but also important systemic long-term effects. At the end of the review we finally report the possible options of treatment considering however that at present there are no ideal therapies or evaluations, and decisions have to be made on a case by case basis.