Antipsychotic treatment of primary delusional parasitosis: systematic review.

BACKGROUND Little is known about the treatment of delusional parasitosis with typical and atypical antipsychotics. AIMS To evaluate the effectiveness of typical and atypical antipsychotics in primary delusional parasitosis (delusional disorder, somatic type). METHOD A systematic review was conducted. RESULTS No randomised trials were found and hence we collected the best evidence from 16 other trials and case reports, separating primary from other forms of delusional parasitosis. Studies using typical antipsychotics showed partial or full remission in between 60 and 100% of patients. Analysis of selected patients with primary delusional parasitosis showed that typical and atypical antipsychotics were effective in the majority, but that remission rates did not differ significantly between typical and atypical antipsychotics. CONCLUSIONS In the absence of controlled trials there is limited evidence that antipsychotics are effective in primary delusional parasitosis. Rigorous studies are needed to evaluate their effectiveness and to compare typical and atypical antipsychotics directly.