Description_x000D_ Packaging_x000D_ 10, 50 mg in glass bottle_x000D_ Biochem/physiol Actions_x000D_ Alosetron is a potent and highly selective antagonist of serotonin 5-HT3 receptors, nonselective cation channels found predominantly in the enteric nervous system of the gastrointestinal tract. These receptors are involved in the regulation of visceral pain, colonic transit and GI secretions that can contribute to the pathophysiology of irritable bowel syndrome (IBS). Alosetron is used clinically for treatment of women with severe diarrhea-predominant IBS.