Nobody knows what causes fibromyalgia, it is thought that some people have a predisposition to the condition which is then triggered by a physical, emotional or mental trauma. Because there is no physical damage, the fundamental nature of fibromyalgia is hard to pinpoint - it is felt that there is a problem with the main pain receptors in the body but nobody has been able to identify what this may be.
People with rheumatoid arthritis and lupus are particularly likely to develop fibromyalgia.
The National Institute of Arthritis and Musculoskeletal and Skin Diseases states that "Some scientists speculate that a person's genes may regulate the way his or her body processes painful stimuli. According to this theory, people with fibromyalgia may have a gene or genes that cause them to react strongly to stimuli that most people would not perceive as painful. However, those genes—if they, in fact, exist—have not been identified."
One hypothesis is that the condition is brought about by the loss of deep sleep which creates a deficiency in serotonin which in turn results in a heightened sensitivity to pain.
Nobody knows if there is a causal link between loss of deep sleep and pain related alterations in the central nervous system but many people report that their condition was initiated by a bout of physical or mental stress. Some people have put forward the hypothesis that fibromyalgia is the result of a virus attacking the body's autoimmune system.
Elevated levels of nerve growth factor and a nerve chemical signal known as substance P have been found in the spinal fluid of people with fibromyalgia. Relatively low levels of the brain nerve chemical serotonin are also found in fibromyalgia patients.
The NHS site says that "There may not be any one cause, and it may be that several factors interact to cause fibromyalgia."
