More than 3 million US cases per year Fibromyalgia is a chronic disorder characterized by widespread musculoskeletal pain, fatigue, and tenderness in localized areas and is often accompanied by altered sleep, memory, and mood swings. Although the causes of fibromyalgia are unknown, there may be a number of factors involved. Fibromyalgia has been linked to: Stressful or traumatic events, such as car accidents, repetitive injuries, illness or certain diseases, or can also occur