This is because no evidence appears on X-rays or in laboratory tests. People with fibromyalgia often look healthy. Some doctors may conclude that patients have psychological problems. There are 18 such points for doctors to test, spots where healthy people wouldn't feel pain if touched. Skeptics suggest that many people feel tenderness on those spots and that its measurement is subjective, but McCain said a doctor can determine tenderness with the same reliability as blood pressure if the exam is done properly.
Many researchers believe that fibromyalgia is an abnormality in the way the body handles pain.
In fibromyalgia patients, pain stimuli come in normally, but the brain doesn't turn off the pain with its usual effectiveness. Some researchers believe that injury, physical or emotional trauma or even an infection, such as a flu virus, may trigger fibromyalgia. Some believe it is related to a lack of growth hormone, produced at night by the pituitary gland and used to repair muscles. Without such repair, muscles are sore, the theory goes. Treatment for fibromyalgia involves symptom relief.