Duloxetine is a serotonin-norepinephrine reuptake inhibitor (SNRI) which is FDA approved for the treatment of generalized anxiety disorder (GAD) in doses of 30 mg to 120 mg daily. Duloxetine has been shown to significantly improve symptoms of GAD as measured through the Hamilton Anxiety Rating Scale (HAMA), the Clinical Global Impressions Scale (CGI-I), and other various outcome measures in several placebo-controlled, randomized, double blind, multi-center studies. Symptom improvement began within the first few weeks, and continued for the duration of the studies. In addition, duloxetine has also been shown to improve outcomes in elderly patients with GAD, and in GAD patients with clinically significant pain symptoms. Duloxetine was noninferior compared with venlafaxine XR. Duloxetine was found to have a good tolerability profile which was predictable and similar to another SNRI, venlafaxine. Adverse events (AEs) such as nausea, constipation, dry mouth, and insomnia were mild and transient, and occurred at relatively low rates. It was found to have a low frequency of drug interactions. In conclusion, duloxetine, a selective inhibitor for the serotonin and norepinephrine transporters, is efficacious in the treatment of GAD, and has a predictable tolerability profile, with AEs generally being mild to moderate.
Keywords: GAD; anxiety; duloxetine; generalized anxiety disorder.