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Obsessive-Compulsive Disorder (OCD)


Katharine Anne Phillips

, MD, Weill Cornell Medical College;

Dan J. Stein

, MD, PhD, University of Cape Town

Reviewed/Revised Jan 2021 | Modified Sep 2022
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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 plus, in many cases, cognitive therapy), drug therapy (specifically, selective serotonin reuptake inhibitors [SSRIs] or clomipramine), or, especially in severe cases, both.

Overview of Obsessive-Compulsive Disorder (OCD)

General reference

Symptoms and Signs of OCD

Obsessions are unwanted, intrusive thoughts, urges, or images, the presence of which usually causes marked distress or anxiety. The dominant theme of the obsessive thoughts may be harm, risk to self or others, contamination, doubt, symmetry, or aggression. For example, patients may obsess about becoming contaminated with dirt or germs unless they wash their hands for 2 hours a day. The obsessions are not pleasurable. Thus, patients usually 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

  • Washing (eg, handwashing, showering)

  • Checking (eg, that the stove is turned off, that doors are locked)

  • Counting (eg, repeating a behavior a certain number of times)

  • Ordering (eg, arranging tableware or workspace items in a specific pattern)

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 (eg, 1 hour a 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 obsessive-compulsive disorder (OCD) recognize to at least 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 may fear embarrassment or stigmatization, they often conceal their obsessions and rituals. Relationships may be disrupted, and performance in school or at work may decline. Depression is a common secondary feature.

Many people with OCD have coexisting psychologic disorders, including

More than one quarter to about two thirds of people with OCD have suicidal thoughts at some point, and 10 to 13% attempt suicide (see Suicidal Behavior Suicidal Behavior Suicide is death caused by an intentional act of self-harm that is designed to be lethal. Suicidal behavior encompasses a spectrum of behavior from suicide attempt and preparatory behaviors... read more ). Risk of an attempt is increased if people also have major depressive disorder.

Diagnosis of OCD

  • Clinical criteria

Diagnosis of obsessive-compulsive disorder is clinical, based on the presence of obsessions, compulsions, or both. The obsessions or compulsions must be time-consuming (eg, > 1 hour a day) or cause clinically significant distress or impairment of functioning.

Treatment of OCD

  • Exposure and ritual (response) prevention therapy; cognitive therapy is often added

  • Selective serotonin reuptake inhibitor (SSRI) or clomipramine, plus, if needed, an augmenting medication

Exposure and ritual prevention therapy is often effective in patients with obsessive-compulsive disorder; its essential element is gradually exposing patients to situations or people that trigger the anxiety-provoking obsessions and rituals while asking them not to perform their rituals. For example, a patient with contamination obsessions and washing compulsions may be asked to touch a toilet seat without washing her hands. 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).

Cognitive therapy techniques (eg, cognitive restructuring) may also be useful in targeting some symptoms of obsessive-compulsive disorder.

SSRIs Selective Serotonin Reuptake Inhibitors (SSRIs) Several drug classes and drugs can be used to treat depression: Selective serotonin reuptake inhibitors (SSRIs) Serotonin modulators (5-HT2 blockers) Serotonin-norepinephrine reuptake inhibitors... read more 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. Some patients who do not substantially improve with adequate trials of these drugs may benefit from addition of augmenting medication such as an atypical neuroleptic (eg, aripiprazole) or a glutamate modulator (eg, memantine, N-acetylcysteine). There are more supporting data for atypical neuroleptics as SSRI-augmenting agents than for other medications.

Many experts believe that combining exposure and ritual prevention with drug therapy is best, especially for severe cases.

Key Points

  • Obsessions are intrusive, unwanted thoughts, images, or urges that usually cause marked distress or anxiety.

  • Compulsions are excessive, repetitive rituals that people feel they must do to reduce the anxiety caused by their obsessive thoughts or to neutralize their obsessions.

  • Obsessions and/or compulsions must be time-consuming (eg, > 1 hour a day, often much more) or cause patients significant distress or impairment in functioning.

  • Treat by gradually exposing patients to situations that trigger the anxiety-provoking obsessions and rituals while requiring them not to perform their rituals. The addition of cognitive approaches to exposure and response prevention may be helpful.

  • Giving an SSRI or clomipramine, often at relatively high doses, is often effective.

Drugs Mentioned In This Article

Drug Name Select Trade
Abilify, Abilify Asimtufii, Abilify Discmelt, Abilify Maintena, Abilify Mycite, Aristada
Namenda, Namenda XR
Acetadote, CETYLEV, Mucomyst, Mucosil Acetylcysteine
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