A review of delusions of parasitosis, part 1: presentation and diagnosis.

Delusions of parasitosis (DOP), a psychiatric disorder in which patients erroneously insist that they are infested with parasites, remains a fascinating entity with elusive origins. Typically, these patients are resistant to psychiatric referral and treatment with psychotropic medications. We discuss the classification, epidemiology, clinical presentation, etiology, associated features, and differential diagnosis of this disorder. The authors reviewed case reports and clinical trials and tabulated the epidemiologic data, which show DOP is more common than previously thought.