Fibromyalgia syndrome is a condition that can cause muscle pain throughout the body. Fibromyalgia syndrome causes not only muscles, but ligaments and tendons may also be affected. Symptoms of fibromyalgia syndrome include pressure points in multiple muscles in the body, and pressure and tenderness may be present in multiple areas of the body. In addition to muscle pain there may be fatigue, poor sleep, flu-like symptoms, headaches, anxiety, nervousness, depression, stomach pain, abdominal pain, diarrhea, constipation, frequent urination, urinary urgency, and sleep disturbances. It is generally most common in women, most often seen in people who are in a bad mood, most often with anxiety or depression, and does not respond well to general analgesic medication. Fibromyalgia syndrome is not clearly diagnosed by ancillary tests, and all laboratory tests, tests, and imaging tests are negative. The diagnosis of fibromyalgia syndrome relies on a detailed history and physical examination by the clinician, as well as the use of various ancillary tests to identify the syndrome, except for tests that can cause peripheral muscle pain.