Current status of atypical antipsychotics for the treatment of fibromyalgia.

The treatment of fibromyalgia requires pharmacological and nonpharmacological therapies. The pharmacological treatment of fibromyalgia is limited to a few drugs that have been demonstrated to be moderately effective in some but not all dimensions of the disease. Therefore, the search for new drugs to treat this condition is warranted. Atypical antipsychotics offered an attractive alternative because they had been shown to be active against several key symptoms of fibromyalgia. The results of open-label studies, however, appear to indicate that atypical antipsychotics are poorly tolerated in patients with fibromyalgia, and only quetiapine XR has been studied in randomized controlled trials. Quetiapine XR has demonstrated effectiveness in treating comorbid major depression, anxiety and sleep disturbance. However, in two randomized controlled trials, quetiapine XR was not differentiated from placebo and failed to demonstrate noninferiority to amitriptyline in terms of improving overall symptomatology. The effect of quetiapine XR on pain and its usefulness as part of a combination pharmacological regimen should be further evaluated. Overall, the use of quetiapine (initiated at a low dose and slowly titrated) in fibromyalgia should be limited to patients with comorbid major depression or patients who are currently receiving other treatments and have unresolved and disabling depressive and/or anxiety symptoms.