title: Risperidone and megacolon.
abstract: Risperidone is an atypical anti-psychotic medication with both 5HT2 receptor and D2 dopamine receptor antagonism. Its use has been reported to be generally safe with very few gastro-intestinal (GI) adverse or side effects. In this paper, we describe a case of megacolon associated with the use of risperidone. A 44-year-old man suffering from schizophrenia was treated with risperidone and developed gross abdominal distension after twenty-five days. Abdominal X-ray and colonoscopy showed megacolon. He improved following a surgical decompression and a reduction of risperidone dosage. We discuss the neuro-electro-physiological mechanisms of gastro-intestinal motility and conclude that the risperidone-associated megacolon may be dose-related and that there should be a heightened awareness of such possible GI complication when using risperidone.
authors.affiliation: Department of General Psychiatry, Institute of Mental Health, Woodbridge Hospital, Singapore 539747. dominic.lim@chmeds.ac.nz
authors.forename: D K
authors.initials: DK
authors.lastname: Lim
authors.forename: R
authors.initials: R
authors.lastname: Mahendran
mesh_terms: D000328:Adult; D014150:Antipsychotic Agents / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008531:Megacolon / Q000139:chemically induced* / Q000601:surgery; D018967:Risperidone / Q000009:adverse effects*
chemical_list: D014150:Antipsychotic Agents; D018967:Risperidone