Fibromyalgia

Fibromyalgia is a syndrome characterized by the following diagnostic criteria:
*Widespread pain, lasting for more than three months and affecting all four quadrants of the body (above and below the waist on both the right and left sides)
*Tenderness at most of the eighteen sites associated with the diagnosis (although other spots may be tender as well)
It may also be characterized by additional symptoms such as peripheral neuropathy, muscle spasms, muscle weakness, twitching, nerve pain, palpitations, bowel disturbances, and sleep disturbances. It is also associated with cognitive function disturbance such as difficulties with memory, concentration, anxiety and depression.
Fibromyalgia is a diagnosis of exclusion requiring a differential diagnosis and then excluding everything else that could cause the symptoms with medical tests. There is no definitive test for fibromyalgia - indeed all the patient's test results will look normal. 
The cause of fibromyalgia is unknown, but it is often associated with other stress disorders, particularly post-traumatic stress disorder. There also appears to be a genetic component as the disorder runs in families. There is also a belief that it is caused by a major depressive episode.
There is no cure for fibromyalgia and treatment is focussed on dealing with the symptoms. The best therapies appear to be a mix of medication, education, moderate physical exercise and cognitive therapy. However, the disease often makes it difficult for patients to work or have normal leisure activities. They also tend to require frequent medical care.