Efficacy and safety of quetiapine treatment for delusional parasitosis: experience in an elderly patient.

Delusional parasitosis is an unusual psychiatric disorder characterized by the false and persistent belief of being infested by parasites. Treatments include haloperidol, pimozide, and at present, olanzapine and risperidone. We report a case of delusional parasitosis in an elderly man, in which the treatment with low doses of quetiapine induced the complete remission of the syndrome, without any considerable side effects. No such report has been described before.