Obsessive–compulsive disorder (OCD) is a mental and behavioral disorder in which an individual has intrusive thoughts, or an obsession and feels the need to perform certain routines/compulsions repeatedly to relieve the distressed caused by the obsession, to the extent where it impairs general function. Obsessions are persistent unwanted thoughts, mental images, or urges that generate feelings of anxiety, disgust, or discomfort. Common obsessions include fear of contamination, obsession with symmetry, the fear of acting blasphemously, their own sexual orientation, and the fear of possibly harming others or themselves. Compulsions are repeated actions or routines that occur in response to obsessions to achieve a relief from anxiety. Common compulsions include excessive hand washing, cleaning, counting, ordering, avoiding triggers, hoarding, neutralizing, seeking assurance, praying, and checking things. People with OCD may only perform mental compulsions, this is called primarily obsessional obsessive–compulsive disorder (Pure O). Many adults with OCD are aware that their compulsions do not make sense, but they perform them anyway to relieve the distress caused by obsessions. Compulsions occur often, typically taking up at least one hour per day and impairing one's quality of life. The cause of OCD is unknown. There appear to be some genetic components, and it is more likely for both identical twins to be affected than both fraternal twins. Risk factors include a history of child abuse or other stress-inducing events; some cases have occurred after streptococcal infections. Diagnosis is based on presented symptoms and requires ruling out other drug-related or medical causes; rating scales such as the Yale–Brown Obsessive Compulsive Scale (Y-BOCS) assess severity. Other disorders with similar symptoms include generalized anxiety disorder, major depressive disorder, eating disorders, tic disorders, and obsessive–compulsive personality disorder. The condition is also associated with a general increase in suicidality. Treatment for OCD may involve psychotherapy such as cognitive behavioral therapy (CBT), pharmacotherapy such as antidepressants, or surgical procedures such as deep brain stimulation. CBT increases exposure to obsessions and prevents compulsions, while metacognitive therapy encourages ritual behaviors to alter the relationship to one's thoughts about them. Selective serotonin reuptake inhibitors (SSRIs) are a common antidepressant used to treat OCD. SSRIs are more effective when used in excess of the recommended depression dosage; however, higher doses can increase side effect intensity. Commonly used SSRIs include sertraline, fluoxetine, fluvoxamine, paroxetine, citalopram, and escitalopram. Some patients fail to improve after taking the maximum tolerated dose of multiple SSRIs for at least two months; these cases qualify as treatment-resistant and require second-line treatment such as clomipramine or atypical antipsychotic augmentation. Surgery may be used as a final resort in the most severe or treatment-resistant cases, though most procedures are considered experimental due to the limited literature on their side effects. Without treatment, OCD often lasts decades. Obsessive–compulsive disorder affects about 2.3% of people at some point in their lives, while rates during any given year are about 1.2%. It is unusual for symptoms to begin after age 35, and around 50% of patients experience detrimental effects to daily life before age 20. Males and females are affected equally, and OCD occurs worldwide. The phrase obsessive–compulsive is sometimes used in an informal manner unrelated to OCD to describe someone as excessively meticulous, perfectionistic, absorbed, or otherwise fixated. However, the actual disorder is not characterized by that, and many individuals with OCD may be dirty, unclean, or uncaring about disease/symmetry.
