Anxiety Disorders: Obsessive-Compulsive Disorder

Obsessive-compulsive disorder (OCD) is classified as an anxiety disorder. It is usually characterized by the presence of two distinct phenomena: obsessions and compulsions. It is considered a common disorder with a 2.5% prevalence. Earlier age of onset, before age 18, has been associated with an increased risk in first-degree relatives. Neuroimaging studies have implicated abnormalities in the orbitofrontal cortex, anterior cingulate cortex, and structures of the basal ganglia and thalamus. Several different lines of investigation support a serotonin hypothesis for OCD. Both pharmacologic and behavioral therapies have proved effective for OCD. Pharmacologic agents used to treat OCD include the SRIs clomipramine, fluoxetine, fluvoxamine, sertraline, paroxetine, citalopram, and escitalopram. Behavioral therapy is effective both as a primary treatment and an augmentation agent. Behavior therapy is based on the principles of exposure and response prevention. Although the majority of patients, perhaps as many as 85%, experience some improvement, most patients do not experience complete remission.