The fibromyalgia syndrome (FMS) is an ill-defined clinical disorder characterized by widespread pain and diffuse tenderness which is assessed at specified anatomical locations. The FMS is 10 times more common in females, and its prevalence in the community increases from two percent at age 20 to eight percent at age 70. Although the American College of Rheumatology (ACR) has defined classification criteria for the diagnosis of the FMS its' pathogenesis remains vague. Diffuse and persistent musculoskeletal pain, consistent with the mentioned ACR criteria have also been reported among patients with other ill defined medical conditions such as migraines, chronic fatigue pain, myofascial pain, irritable bowel syndrome which presentation often overlaps with the FMS.