Obsessive-compulsive disorder (OCD) is a neuropsychiatric disorder characterized by obsessions and/or compulsions that are distressing, time consuming or significantly impairing. It is the fourth most common psychiatric illness1 with a lifetime prevalence of 1-3%.2, 3 OCD was identified as the anxiety disorder with the highest proportion (50.6%) of serious cases by the National Comorbidity Study Replication4 and as a leading global cause of non-fatal illness burden by the World Health Organization (WHO) in 2006.5
