Ischemic colitis during treatment with alosetron

Irritable bowel syndrome (IBS) is one of the most common entities observed by both primary care physicians and gastroenterologists. Alosetron is a pot ent and selective serotonin antagonist that recently became the first Food and Drug Administration-approved agent for diarrhea-predominant IBS. Howeve r, since approval, significant side effects have been noted with the use of alosetron including severe constipation, fecal impaction, and ischemic col itis. We describe a case of ischemic colitis in a male patient with IDS who was briefly treated with alosetron. Clinical, endoscopic, and pathologic f eatures of the focal colitis strongly suggested ischemia. Symptoms correlat ed temporally with alosetron use, and symptoms abated with discontinuation of the drug. Endoscopic and pathologic resolution of the colitis were docum ented.