An expanding body of clinical experience and controlled trials has established the efficacy of serotonin selective reuptake inhibitors (SSRIs) and the serotonin norepinephrine reuptake inhibitor (SNRI) venlafaxine, for the treatment of social anxiety disorder, with paroxetine, sertraline and venlafaxine extended-release (XR), which are FDA approved for this indication. The newest SNRI, duloxetine, has been shown to be effective at doses of 60mg/day to 120mg/day for anxiety associated with depression, and is anticipated to be a broad spectrum agent for mood and anxiety disorders (Dunner, Goldstein, Mallinckrodt, Lu, & Detke, 2003). However, no data on the efficacy of duloxetine for Social Anxiety Disorder, nor guidance regarding time to response or predictors of response, is yet available. These questions are the focus of this proposal.~This is a two phase, 24-week research study in which participants who remain symptomatic at the end of one phase (6 weeks) enter into the next phase. In phase I, all participants receive 60mg/day of duloxetine (Cymbalta) for 6 weeks. Participants who continue to have anxiety symptoms will enter the 18-week Phase II, in which they continue taking 60 mg/day of duloxetine and they will also be randomly assigned (by chance, like a flip of a coin) to receive either an additional 60mg/day of duloxetine or placebo (contains no active medication).
The purpose of this study is to examine the safety and efficacy of duloxetine for the treatment of social anxiety disorder.