This document provides information on anxiety disorders, including definitions, classifications, epidemiology, symptoms, pathophysiology, treatment options and specific details on generalized anxiety disorder, panic disorder, phobic disorders, post-traumatic stress disorder, and obsessive-compulsive disorder. It discusses the role of the GABA, serotonin and norepinephrine systems in the pathophysiology of anxiety disorders. It also summarizes pharmacological treatments including SSRIs, TCAs, MAOIs, benzodiazepines, and buspirone as well as cognitive behavioral therapy.