Fibromyalgia is a chronic disorder which is characterized by widespread pain, tenderness and fatigue. Persons with fibromyalgia may also experience sleep disturbances, morning stiffness, anxiety, and irritable bowel syndrome. Often it is also accompanied by depression. It is difficult to diagnose because most of the symptoms mimic those of other disorders. Fibromyalgia is NOT an autoimmune disease, however it does accompany other autoimmune rheumatic and endocrine diseases.