Fibromyalgia syndrome and serotonin.

Although disturbances in the musculoskeletal system, in the neuroendocrine system and in the central nervous system (CNS) have been implicated in the pathophysiology of fibromyalgia syndrome (FMS), the primary mechanisms underlying the etiopathogenesis of FMS remain elusive. It has been postulated that disturbances in serotonin metabolism and transmission, along with disturbances in several other chemical pain mediators, are present in patients with FMS. In this article we review published studies on the pathophysiological role of serotonin in FMS. Although studies that indirectly measured the function of serotonin in the CNS in FMS revealed some abnormalities in the metabolism and transmission of serotonin, the role of serotonin in the pathophysiology of syndrome remains inconclusive and warrants more studies.