Obsessive-compulsive disorder (OCD) is characterized by recurrent, persistent, unwanted, and intrusive thoughts, urges, or images (obsessions) and/or by repetitive behaviors or mental acts that patients feel driven to do (compulsions) to try to lessen or prevent the anxiety that obsessions cause. Diagnosis is based on history. Treatment consists of psychotherapy (specifically, exposure and response prevention), drug therapy (specifically, SSRIs or clomipramine), or, especially in severe cases, both.
OCD is slightly more common among women than men and affects about 1 to 2% of the population. Up to 30% of people with OCD also have a past or current tic disorder (see Tic Disorders and Tourette Syndrome in Children and Adolescents).
Symptoms and Signs
Obsessions are unwanted, intrusive thoughts, urges, or images, the presence of which usually cause marked distress or anxiety. The dominant theme of the obsessive thoughts may be harm, risk to self or others, danger, contamination, doubt, loss, or aggression. For example, patients may obsess about becoming contaminated with dirt or germs unless they wash their hands for ≥ 2 h a day. The obsessions are not pleasurable. Thus, patients try to ignore and/or suppress the thoughts, urges, or images. Or they try to neutralize them by performing a compulsion.
Compulsions (often called rituals) are excessive, repetitive, purposeful behaviors that affected people feel they must do to prevent or reduce the anxiety caused by their obsessive thoughts or to neutralize their obsessions. Examples are
Most rituals, such as hand washing or checking locks, are observable, but some mental rituals, such as silent repetitive counting or statements muttered under the breath, are not. Typically, the compulsive rituals must be done in a precise way according to rigid rules. The rituals may or may not be connected realistically to the feared event. When connected realistically (eg, showering to avoid being dirty, checking the stove to prevent fire), the compulsions are clearly excessive—eg, showering for hours each day or always checking the stove 30 times before leaving the house. In all cases, the obsessions and/or compulsions must be time-consuming (> 1 h/day, often much more) or cause patients significant distress or impairment in functioning; at their extreme, obsessions and compulsions may be incapacitating.
The degree of insight varies. Most people with OCD recognize to some degree that the beliefs underlying their obsessions are not realistic (eg, that they really will not get cancer if they touch an ashtray). However, occasionally, insight is completely lacking (ie, patients are convinced that the beliefs underlying their obsessions are true and that their compulsions are reasonable).
Because people with this disorder fear embarrassment or stigmatization, they often conceal their obsessions and rituals. Relationships often deteriorate, and performance in school or at work may decline. Depression is a common secondary feature.
Diagnosis is clinical, based on the presence of obsessions, compulsions, or both. The obsessions or compulsions must be time-consuming or cause clinically significant distress or impairment of functioning.
Exposure and ritual prevention therapy is often effective; its essential element is gradually exposing patients to situations or people that trigger the anxiety-provoking obsessions and rituals while requiring them not to perform their rituals. This approach allows 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, some patients have incomplete responses (as some also do to drugs).
Certain antidepressants, including SSRIs (see Selective serotonin reuptake inhibitors (SSRIs)) and clomipramine (a tricyclic antidepressant with potent serotonergic effects), are often very effective. Patients often require higher doses than are typically needed for depression and most anxiety disorders. Many experts believe that combining exposure and ritual prevention with drug therapy is best, especially for severe cases.
Last full review/revision March 2014 by Katharine A. Phillips, MD; Dan J. Stein, MD, PhD
Content last modified March 2014