An open clinical trial of venlafaxine treatment of fibromyalgia.

Of 15 patients with fibromyalgia who were first evaluated for the presence of Axis I psychiatric diagnoses by use of the Structured Clinical Interview for DSM-IV, 11 completed an open 8-week trial with the novel antidepressant venlafaxine. Six (55%) of 11 completers experienced a > or = 50% reduction of fibromyalgia symptoms. The presence of lifetime psychiatric disorders, particularly depressive and anxiety disorders, predicted a positive response to venlafaxine. These findings suggest that it is important to assess for comorbid psychiatric disorders in patients with fibromyalgia and that venlafaxine may be helpful to some of these patients.