BACKGROUND: Escitalopram 10 mg/day is an effective and well-tolerated antidepressant. Three randomized controlled trials recently evaluated the safety and efficacy of escitalopram in the treatment of generalized anxiety disorder (GAD). METHODS: The trial designs were virtually identical, allowing data to be pooled across studies. Male and female outpatients, ages 18-80 years, with DSM-IV-defined GAD were randomized to double-blind treatment with escitalopram or placebo for 8 weeks. Escitalopram dose was fixed at 10 mg/day for the first 4 weeks, after which increases to 20 mg/day were permitted. The primary efficacy variable was the mean change from baseline in total Hamilton Anxiety Scale (HAMA) score. RESULTS: Approximately 850 patients were randomized to double-blind treatment. In each individual study, escitalopram was significantly superior to placebo (p<0.05) as measured by change from baseline in HAMA score. By-visit analyses of data pooled across studies revealed significantly greater improvement (p<0.05) in the escitalopram group beginning at week 1 or 2 and continuing through week 8 for all primary and secondary efficacy variables. The mean change in HAMA total score from baseline to endpoint also was significantly greater for patients maintained at escitalopram 10 mg/day than for those receiving placebo. Escitalopram was generally well tolerated. LIMITATIONS: The studies included in this analysis were of short-term duration and excluded patients with significant medical and psychiatric comorbidities, such as major depressive disorder. CONCLUSION: Results from the individual trials and the pooled analysis demonstrate that escitalopram is effective and well tolerated for the treatment of GAD.