Severe Anxiety. Obsessions are thoughts and images which produce anxiety. Compulsions are behaviors which respond to this and attempt to reduce or avoid anxiety. It is the intensity frequency and repetitive nature which leads to a disorder.
Two Symptoms. Obsessive-compulsive disorder is an anxiety disorder with two predominant symptoms. The first is an obsession, an unwanted thought, fear, or urge to do a behavior. The second is a compulsion, a ritualized behavior that is performed to reduce the anxiety caused by an obsession. Patients know these symptoms are irrational but cannot control them. These is effective treatment.