: 210

Notable cases
John Bunyan (1628–1688), the author of The Pilgrims Progress, displayed symptoms of OCD (which had not yet been named). During the most severe period of his condition, he would mutter the same phrase over and over again to himself while rocking back and forth. : 53–54  He later described his obsessions in his autobiography Grace Abounding to the Chief of Sinners, stating, "These things may seem ridiculous to others, even as ridiculous as they were in themselves, but to me they were the most tormenting cogitations. ": 53–54  He wrote two pamphlets advising those with similar anxieties. : 217–218  In one of them, he warns against indulging in compulsions: "Have care of putting off your trouble of spirit in the wrong way: by promising to reform yourself and lead a new life, by your performances or duties". : 217–218 British poet, essayist and lexicographer Samuel Johnson (1709–1784) also had OCD. He had elaborate rituals for crossing the thresholds of doorways, and repeatedly walked up and down staircases counting the steps. : 54–55  He would touch every post on the street as he walked past, only step in the middles of paving stones, and repeatedly perform tasks as though they had not been done properly the first time. : 55 The American aviator and filmmaker Howard Hughes is known to have had OCD. Friends of Hughes have also mentioned his obsession with minor flaws in clothing. This was conveyed in The Aviator (2004), a film biography of Hughes.English singer-songwriter George Ezra has openly spoken about his life-long struggle with OCD, particularly "Pure OCD.
Compulsions occur so often, typically taking up at least one hour per day, that they impair ones 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 ones 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.