Anxiety disorders are a group of disorders characterized by symptoms of excessive anxiety and/or fear. Anxiety itself, unlike fear, is persistent and concerns future events. There are many types of anxiety disorders, including generalized anxiety disorder, social anxiety disorder, phobias such as fear of flying or agoraphobia, and panic disorder. Note: Examine has separate pages for the anxiety disorders just listed. The Examine Database on this page covers studies in people with other anxiety disorders, unspecified anxiety disorders, or mixed anxiety disorders.