The psychopharmacology of fibromyalgia: a drug development perspective.

The fibromyalgia syndrome (FMS) is the most frequent cause of chronic widespread pain. In this review, we summarize the state of the art on the syndrome and its pathophysiology, with an emphasis on identifying bases for the development of novel therapies. Toward this end, the anatomy and physiology of pain pathways are summarized, followed by a review of the altered biology of pain processing, neurotransmitter function, and neuroendocrine systems in FMS. The categories of drugs currently employed to treat the disorder are detailed, along with a critical review of the literature supporting such use. Throughout the article, FMS is compared with and related to both major depressive disorder and neuropathic pain, conditions that may share some common biological processes with FMS but for which new drug discovery efforts are significantly more active due to the more established nature of these diagnoses.