CBT is an empirically supported psychotherapy that has been found to be effective in treating GAD in approximately 50 percent of patients enrolled in controlled clinical trials. However, a substantial proportion (nearly half) of individuals with GAD do not achieve full remission or clinically significant improvement at the cessation of CBT. Escitalopram (Lexapro)is a selective serotonin reuptake inhibitor (SSRI) antidepressant, which has been shown to be effective in treating GAD in several large-scale controlled clinical trials. The Food and Drug Administration has approved ecitalopram for the treatment of GAD.