Obsessive-compulsive disorder is characterized by recurring, unwanted, anxiety-provoking, intrusive ideas, images, or impulses (obsessions) that may even seem silly, weird, nasty, or horrible to the person experiencing them. The person also has urges (compulsions) to do something that will relieve the discomfort caused by the obsessions.

• Most obsessive-compulsive behavior is related to concerns about harm or risk.
• Treatment may include exposure therapy (with prevention of compulsive rituals) and antidepressants.

Obsessive-compulsive disorder occurs about equally in men and women and affects about 2% of the population. Children are also affected (see Mental Health Disorders in Children: Obsessive-Compulsive Disorder).

The obsessions are usually related to a sense of harm, risk, or danger. Common obsessions include the following:

• Concerns about contamination (for example, worrying that touching doorknobs will cause disease)
• Doubts (for example, worrying that the front door was not locked)
• Fear of loss (for example, loss of money or a loved one)
• Fear of becoming aggressive and physically injuring someone

More than 95% of people with obsessive-compulsive disorder feel a compulsion to perform rituals—repetitive, purposeful, intentional acts. Rituals used to control an obsession include the following:

• Washing or cleaning to be rid of contamination
• Checking to allay doubt (for example, checking to make sure a door is locked)
• Hoarding to prevent loss
• Avoiding the people who might become objects of aggression

Most rituals, such as excessive hand washing or repeated checking to make sure a door has been locked, can be observed. Other rituals, such as repetitive counting or quietly mumbling statements intended to diminish danger, cannot be observed. Obsessions are not always accompanied by compulsions.

Most people with obsessive-compulsive disorder are aware that their obsessive thoughts do not reflect actual risks and that their compulsive behaviors are ineffective. Obsessive-compulsive disorder, therefore, differs from psychotic disorders, in which people lose contact with reality. Obsessive-compulsive disorder also differs from obsessive-compulsive personality disorder (see Personality Disorders: Obsessive-compulsive personality disorder), in which specific personality traits are defined (for example, being a perfectionist). People with obsessive-compulsive disorder are aware that their compulsive behaviors are excessive to the point of being bizarre, and they are afraid they will be embarrassed or stigmatized. Thus, they often perform their rituals secretly, even though the rituals may occupy several hours each day.

About one third of people with obsessive-compulsive disorder are depressed at the time the disorder is diagnosed. Altogether, two thirds become depressed at some point.

Did You Know... Most people with obsessive-compulsive disorder know that their obsessions and compulsions are irrational.

Treatment

Exposure therapy is somewhat effective in treating obsessive-compulsive disorder. Exposure therapy involves repeatedly exposing people to whatever (situations or people) triggers obsessions, rituals, or discomfort but not letting them perform the compulsive ritual. Discomfort or anxiety gradually diminishes during repeated exposure as people learn that rituals are unnecessary for decreasing discomfort. The improvement usually persists for years, probably because people who have mastered this self-help approach continue to practice it as a way of life without much effort after formal treatment has ended.

Selective serotonin reuptake inhibitors (such as fluoxetine), a type of antidepressant, and clomipramine, a tricyclic antidepressant, are effective. Many experts believe that a combination of exposure therapy (including prevention of rituals) and drug therapy is the best treatment.

Psychodynamic psychotherapy and psychoanalysis have generally not been effective for people with obsessive-compulsive disorder.

Last full review/revision September 2012 by John H. Greist, MD