The cause of fibromyalgia (FM) is unknown but theories pointing toward abnormal hypothalamic pituitary axis function or dysfunction of neurotransmitter pathways in the brain are currently popular.

Several studies have demonstrated different abnormalities in central nervous system functioning. Abnormal sleep studies showing alpha intrusion during delta (stage 4) sleep and a reduction of rapid eye movement (REM) sleep have been seen. In addition, abnormal SPECT scans have suggested lower blood flow to the thalamus and caudate nucleus in the brains of fibromyalgia patients.

Approximately 2 percent of the population has fibromyalgia. About 80 percent of patients with fibromyalgia are women. While fibromyalgia may occur as a primary condition, it is also a secondary condition, occurring in as many as 30 percent of patients with systemic lupus erythematosus and rheumatoid arthritis.

Patients with fibromyalgia complain of generalized pain affecting both sides of the body and both the upper as well as lower part of the body.

Pain tends to be aggravated by weather changes as well as by stress.

While patients will complain of subjective joint swelling, objective swelling is absent.

Sleep disturbance occurs in almost all patients. Complaints of chronic fatigue and non restorative sleep (feeling as if they haven't slept) are common. Sleep apnea may aggravate the situation.

Tender trigger points are noted in all patients. A patient with 11 of 18 tender trigger points fulfills a major diagnostic criterion for the diagnosis of fibromyalgia. These trigger point tender areas are stereotypic meaning the same areas are tender in all patients with the diagnosis of FM..

Other symptoms include migraine headache, decrease in short term memory, cognitive dysfunction, blurred or double vision, hypersensitivity to sound and smells, shortness of breath, chest pains, palpitations, irritable bowel, irritable bladder, painful menses, painful urination, multiple drug allergies, multiple sensitivities to chemicals.

Laboratory testing will not be diagnostic. However, laboratory testing will help to exclude other conditions such as polymyalgia rheumatica, hypothyroidism, rheumatoid arthritis, systemic lupus erythematosus, etc., that might masquerade as fibromyalgia. FM is a diagnosis of exclusion so it is imperative that other possible causes of aches and pains are ruled out.

Imaging tests may also be helpful in establishing the presence or absence of FM.

Treatment must be individualized. Most patients will respond to a combination of non impact aerobic exercise (swimming, stationary bike, elliptical trainer), cognitive behavioral therapy, and medication.

Medications that have been found to be helpful include tricyclic antidepressants in low doses, muscle relaxants such as cyclobenzaprine, also in low doses, and selective serotonin reuptake inhibitors (SSRIs).

Other medicines such as gabapentin and tramadol may also be helpful.