Fibromyalgia is a recently recognized disorder regarded as a common cause of chronic musculoskeletal pain and fatigue.
Diagnosis requires fulfillment of all three major criteria and four or more minor criteria.
Major criteria Generalized aches or stiffness of at least three anatomic sites for at least three months. Six or more typical, reproducible tender points. Exclusion of other disorders which can cause similar symptoms. This drug blocks the enzyme which converts tryptophan to 5-HTP and as a result blocks serotonin production. The researchers discovered that providing headache sufferers with fenclonine resulted in very severe muscle pain.