New treatment options for fibromyalgia: critical appraisal of duloxetine

Fibromyalgia syndrome (FMS) is a chronic condition characterized by widespread pain, tender points, fatigue, and sleep disturbance. FMS leads to high disability levels, poor quality of life, and extensive use of medical care. Effective pharmacological treatment options are rare, and treatment effects are often of limited duration. Duloxetine is a new selective serotonin and norepinephrine reuptake inhibitor that is licensed for the treatment of pain in diabetic neuropathy. So far two randomized, placebo-controlled trials have investigated the short-term safety and efficacy of duloxetine 60 mg/day and 120 mg/day in patients suffering from FMS over a period of 12 weeks. Both dosages were superior to placebo in pain relief, and improvement in quality of life and depressive symptoms. The analgesic effect was largely independent of the antidepressant action of duloxetine. The higher dose of 120 mg/day further reduced the tender point count and elevated the tender point pain thresholds. Only mild to moderate adverse effects were reported. Duloxetine 60 mg/day and 120 mg/day has proven to be beneficial in the treatment of FMS symptoms. As true for other antidepressants further studies are needed to assess the long-term efficacy and safety of duloxetine as an additional pharmacological treatment option in FMS.