Fibromyalgia is a nonarticular rheumatic syndrome of unknown cause characterized by diffuse musculoskeletal aching, pain and stiffness, easy fatigability, multiple discreet tender points, emotional distress, and often, light and restless sleep with intensification of symptoms upon awakening. Symptoms are modulated by environmental, physiologic, and psychological factors. Generally, findings from laboratory tests and roentgenograms are normal. In primary fibromyalgia, no underlying rheumatic or other systemic organic disease is present. Secondary fibromyalgia is a manifestation of underlying disease.