Delusional parasitosis: a new pathway for diagnosis and treatment.

Delusional parasitosis is an uncommon disorder that presents particular challenges to the dermatologist. Patients often resist psychiatric referral. Evidence of efficacy of treatment options is generally weak, but some studies exist. By identifying whether the disorder is primary or secondary to another illness, by attempting to involve the liaison psychiatry team if possible and by treating the patient with a modern antipsychotic, remission is achievable. A pathway for diagnostics and therapy is presented. Treatments of choice are 'atypical' or second-generation antipsychotics such as amisulpride, risperidone or olanzapine in age-appropriate doses. Pimozide is no longer the treatment of choice, owing to a higher risk of adverse drug reactions and lower concordance. In some cases, depot antipsychotics can be considered. For diagnostics and treatment, close collaboration of dermatologists and psychiatrists is recommended.