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Obsessive-compulsive disorder (OCD) is characterized by anxiety-provoking ideas, images, or impulses (obsessions) and by urges (compulsions) to do something that will lessen the anxiety. The cause is unknown. Diagnosis is based on history. Treatment consists of psychotherapy, drug therapy, or, especially in severe cases, both.

OCD occurs about equally in men and women and affects about 2% of the population.

Symptoms and Signs

The dominant theme of the obsessive thoughts may be harm, risk, danger, contamination, doubt, loss, or aggression. Typically, affected people feel compelled to perform repetitive, purposeful rituals to balance their obsessions, as in the following:

• Washing to balance contamination
• Checking to balance doubt
• Hoarding to balance loss
• Avoiding people who may provoke them to balance fear of behaving aggressively

Most rituals, such as hand washing or checking locks, are observable, but some rituals, such as repetitive counting or statements muttered under the breath, are not.

At some point, people with OCD recognize that their obsessions do not reflect real risks and that the behaviors they perform to relieve their concern are unrealistic and excessive. Preservation of insight, although sometimes slight, differentiates OCD from psychotic disorders, in which contact with reality is lost.

Because people with this disorder fear embarrassment or stigmatization, they often conceal their obsessions and rituals, on which they may spend several hours each day. Relationships often deteriorate, and performance in school or at work may decline. Depression is a common secondary feature.

Diagnosis

Diagnosis is clinical based on criteria in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition Text Revision.

Treatment

• Exposure and ritual prevention therapy
• Often antidepressants

Exposure and ritual prevention therapy is effective; its essential element is exposure to situations or people that trigger the anxiety-provoking obsessions and rituals. After exposure, patients forgo rituals, allowing the anxiety triggered by exposure to diminish through habituation. Improvement often continues for years, especially in patients who master the approach and use it even after formal treatment has ended. However, most patients have incomplete responses as they also do to drugs.

Many experts believe that combining psychotherapy and drug therapy is best, especially for severe cases. SSRIs (see Mood Disorders: Selective serotonin reuptake inhibitors (SSRIs)) and clomipramineSome Trade Names
ANAFRANIL
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(a tricyclic antidepressant with potent serotonergic effects) are effective. For most SSRIs, low doses (eg, fluoxetineSome Trade Names
PROZAC
SARAFEM
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20 mg po once/day, fluvoxamineSome Trade Names
LUVOX
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100 mg po once/day, sertralineSome Trade Names
ZOLOFT
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50 mg po once/day, paroxetineSome Trade Names
PAXIL
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40 mg po once/day) are often as effective as larger ones.

Last full review/revision August 2007 by John H. Greist, MD

Content last modified August 2007