Endocrine Abstracts

Drug-induced hyperprolactinaemia is common. Approximately half of those taking antipsychotics develop hyperprolactinaemia due to blockade of the dopamine type 2 receptor. The propensity to cause hyperprolactinaemia varies markedly between antipsychotics. Regular monitoring before and during treatment will identify those with anti-psychotic induced hyperprolactinaemia. If prolactin exceeds 3000 mU/l a pituitary adenoma should be ruled out by MRI. Otherwise treatment is only necessary in cases with symptoms of hyperprolactinaemia or hypogonadism. Treatment options include dose reduction or change in antipsychotic treatment, sex steroid replacement or dopamine agonist therapy which should be done in consultation with psychiatry. By contrast antidepressants may cause modest hyperprolactinaemia in some patients by modulation of serotonin or noradrenaline levels. Routine monitoring is not recommended unless symptoms related to hyperprolactinaemia develop. Management is by dose reduction or switching to an alternative antidepressant with reassessment of prolactin levels and consideration of other causes if prolactin exceeds 1000 mU/l.