Therapeutic update: use of risperidone for the treatment of monosymptomatic hypochondriacal psychosis.

Monosymptomatic hypochondriacal psychoses such as delusions of parasitosis are often difficult to treat. For the past two decades, pimozide has been considered the drug of choice. Although a few controlled studies have been done to support the efficacy of pimozide, the recommendation of treatment of choice is largely based on case reports. Pimozide has significant side effects, including cardiac and extrapyramidal abnormalities, which are of most concern in the treatment of the elderly. Although pimozide does appear to be effective in some cases of somatic delusional disorders, newer antipsychotics such as risperidone have also been shown to be beneficial in treating this perplexing cluster of disorders. Risperidone is generally considered safer than pimozide and should be considered as first-line therapy for monosymptomatic hypochondriacal psychoses.