Trichotillomania and obsessive-compulsive disorder.

Trichotillomania, a disorder characterized by repetitive hair pulling, has been only recently systemically investigated. Such research was encouraged by data that showed obsessive-compulsive disorder, which is also characterized by ritual behaviors, responds selectively to serotonin reuptake inhibitors. In this review, we consider similarities and contrasts in the diagnosis, demographics, phenomenology, neurochemistry, neuropsychiatry, and treatment of trichotillomania and obsessive-compulsive disorder. We argue that a view of trichotillomania as an obsessive-compulsive spectrum disorder that may involve disturbances in grooming behaviors comprises a useful clinical and research heuristic. Nevertheless, there may also be important differences between the two disorders; in particular, trichotillomania has a number of characteristics in common with impulsive disorders. Further empirical investigation is necessary to determine the nature of these complex disorders and their relationship to one another.