Medical treatment of pruritus.

INTRODUCTION: The symptom of chronic pruritus (> 6 weeks of duration) represents a worldwide burden in patients. It is described as the most frequent symptom of the skin complaints and occurs in a broad variety of diseases. However, research on pruritus has been disregarded for a long time, most likely because pruritus used to be considered as a subtype of pain. AREAS COVERED: Although understanding of the epidemiology, clinic and neurobiology of acute and chronic pruritus has considerably expanded in the past years, the therapy of chronic pruritus patients remains challenging. The current guidelines suggest antihistamines, pain modulators, opioid receptor antagonist and antidepressants. Using this, a large number of patients experience relief but mostly no complete resolution. Recent experiences with neurokinin receptor 1 antagonists suggest that target-specific antipruritic drugs are of high efficacy and desirable in chronic pruritus treatments. EXPERT OPINION: New substances and classes of antipruritic drugs are highly needed. Promising candidates are next to neurokinin receptor 1 antagonists, antagonists against the histamine 4 receptor, nerve growth factor receptor or gastrin-releasing peptide receptor.