Anxiety disorder

Anxiety disorders are a group of mental disorders characterized by significant and uncontrollable feelings of anxiety and fear such that a person's social, occupational, and personal functions are significantly impaired. Anxiety may cause physical and cognitive symptoms, such as a sense of impending doom, restlessness, irritability, easy fatigue, difficulty concentrating, increased heart rate, chest pain, abdominal pain, and a variety of other symptoms that vary based on the individual. In casual discourse, the words anxiety and fear are often used interchangeably. In clinical usage, they have distinct meanings; anxiety is clinically defined as an unpleasant emotional state for which the cause is either not readily identified or perceived to be uncontrollable or unavoidable, whereas fear is clinically defined as an emotional and physiological response to a recognized external threat.