The American College of Rheumatology has established two criteria for the diagnosis of fibromyalgia:
- Widespread pain lasting at least three months
- At least 11 positive tender points — out of a total possible of 18
During your physical exam, your doctor may check specific places on your body for tenderness. The amount of pressure used during this exam is usually just enough to whiten the doctor’s fingernail bed. These 18 tender points are a hallmark for fibromyalgia.
While there is no lab test to confirm a diagnosis of fibromyalgia, your doctor may want to rule out other conditions that may have similar symptoms. Blood tests may include:
- Complete blood count
- Erythrocyte sedimentation rate
- Thyroid function tests