Efficacy of olanzapine in social anxiety disorder: a pilot study

Based on evidence suggesting anxiolytic properties of the atypical antipsychotic olanzapine, this study was conducted to evaluate whether olanzapine may be efficacious in treating social anxiety disorder (SAD). This study was an 8-week, double-blind, placebo-controlled evaluation of olanzapine as monotherapy in which 12 patients with the DSM-IV diagnosis of SAD were randomized to either olanzapine (n = 7) or placebo (n = 5). An initial dose of 5 mg/day was titrated to a maximum of 20 mg/day. Baseline to endpoint scores from the Brief Social Phobia Scale (BSPS), Social Phobia Inventory (SPIN), Liebowitz Social Anxiety Scale and Sheehan Disability Scale, as well as Clinical Global Impression-Improvement ratings, were compared for olanzapine versus placebo. Seven subjects completed all 8 weeks of the study, four in the olanzapine group and three in the placebo group. In the intent-to-treat analysis, olanzapine yielded greater improvement than placebo on the primary measures: BSPS (p = 0.02) and SPIN (p = 0.01). Both treatments were well tolerated, although the olanzapine group had more drowsiness and dry mouth. Olanzapine and placebo were both associated with negligible weight gain. Olanzapine was superior to placebo on the primary outcome measures in this preliminary study of SAD. Additional studies of olanzapine as a treatment for SAD are warranted.