Anxiety disorders Anxiety disorders are among the most prevalent mental disorders in the general population. Anxiety disorders can be viewed as a family of related but distinct mental disorders, which include following as classified in the text revision of fourth edition of Diagnostic and Statistical Manual Disorders(DSM-IV-TR): (1) panic disorder with or without agoraphobia; (2) agoraphobia with or without panic disorder; (3) specific phobia; (4) social phobia; (5) obsessive-compulsive disorder; (6) posttraumatic stress disorder; (7) acute stress disorder; (8) generalized anxiety disorder. An acute intense attack of anxiety accompanied by feeling of impending doom is known as panic disorder. The term phobia refer to an excessive fear of a specific object, circumstance, or situation. Obsessivecompulsive disorder is represented by a diverse group of symptoms that include intrusive thoughts, rituals, preoccupations, and compulsions. Posttraumatic stress disorder is a condition marked by development of symptoms after exposure to traumatic life events. Generalized anxiety disorder is defined as excessive anxiety and worry about several events or activities for most days during at least a 6-month period.