Psychogenic excoriation. Clinical features, proposed diagnostic criteria, epidemiology and approaches to treatment.

Psychogenic excoriation (also called neurotic excoriation, acne excoriée, pathological or compulsive skin picking, and dermatotillomania) is characterised by excessive scratching or picking of normal skin or skin with minor surface irregularities. It is estimated to occur in 2% of dermatology clinic patients and is associated with functional impairment, medical complications (e.g. infection) or substantial distress. Psychogenic excoriation is not yet recognised in the DSM. We propose preliminary operational criteria for its diagnosis that take into account the heterogeneity of behaviour associated with psychogenic excoriation and allow for subtyping along a compulsivity-impulsivity spectrum. Psychiatric comorbidity in patients with psychogenic excoriation, particularly mood and anxiety disorders, is common. Patients with psychogenic excoriation frequently have comorbid disorders in the compulsivity-impulsivity spectrum, including obsessive-compulsive disorder, body dysmorphic disorder, substance use disorders, eating disorders, trichotillomania, kleptomania, compulsive buying, obsessive-compulsive personality disorder, and borderline personality disorder. There are few studies of the pharmacological treatment of patients with psychogenic excoriation. Case studies, open trials and small double-blind studies have demonstrated the efficacy of selective serotonin (5-hydroxytryptamine; 5-HT) reuptake inhibitors in psychogenic excoriation. Other pharmacological treatments that have been successful in case reports include doxepin, clomipramine, naltrexone, pimozide and olanzapine. There are no controlled trials of behavioural or psychotherapeutic treatment for psychogenic excoriation. Treatments found to be effective in case reports include a behavioural technique called 'habit reversal'; a multicomponent programme consisting of self-monitoring, recording of episodes of scratching, and procedures that produce alternative responses to scratching; and an 'eclectic' psychotherapy programme with insight-oriented and behavioural components.