25 yr old gentleman has repeated thoughts that he has not locked his car door properly, frequently checks it while driving, he repeatedly checks locks in his house. Diagnosis

Obsessive Compulsive Disorder : Obsession: recurrent and persistent thoughts that are involuntary unwanted, distressing and the individual tries to neutralize them by a thought or action (compulsion). Ex: Contamination(most common), Need for symmetry, Pathological doubt, Sexual compulsion: Act aimed to reduce the anxiety arising out of obsession but fails to do so. Ex: checking(most common), washing, counting, Hoarding, counting. obsession (a door is unlocked )leads to compulsion (checking ), which tries to relieve distress but fails and the obsession-compulsion cycle repeats leading to distress, time consumption. thoughts are one's own thoughts, it may be an idea/urge/image -behavior or mental behavior. M:F- 1:1 age of onset 20-25 years 2-3% prevalence in general population Comorbidity: major depressive disorder, delusional beliefs, overvalued ideas, personality disorder Etiology Psychoanalytical concept*-regression from the oedipal phase to the anal psychosexual phase. Anatomical- altered function in the connections between orbitofrontal coex, caudate, thalamus. Biochemical-*dysregulation of serotonin. Treatment : Pharmacotherapy-Selective serotonin Reuptake InhibitorsSSRI *(fluoxetine, fluvoxamine, paroxetine, seraline) Tricyclic antidepressants TCA(clomipramine) Behavior therapy*: Desensitization, thought stopping, flooding, implosion therapy, aversive conditioning Psychotherapy Surgical cingulotomy*, capsulotomy(e.g., subcaudate tractotomy,). Nonablative surgical techniques like Deep Brain Stimulation *of basal ganglia nuclei Reference: P.605 Kaplan & Sadock's Synopsis of psychiatry clinical Psychiatry, 10th Edition16.4