Anxiety disorders. Focus on obsessive-compulsive disorder.

Obsessive-compulsive disorder was once thought to be rare. Recent epidemiologic surveys reveal the lifetime prevalence rate to be as high as 3%. We now have greater understanding of the neurophysiologic and neurochemical basis of this very crippling disorder. Although obsessive-compulsive disorder often starts in adolescence or early adulthood and can last a lifetime, effective treatment enables most patients to lead relatively normal lives.