Tegaserod

Abstract

▴ Tegaserod is a serotonin (5-hydroxytryptamine; 5-HT) receptor partial agonist which has been investigated for the treatment of irritable bowel syndrome (IBS). Specifically, it binds with high affinity to human 5-HT₄ receptors, thereby stimulating the release of neurotransmitters and the peristaltic reflex in vitro. ▴ Small bowel transit (increased colonic filling over 6 hours) was accelerated in patients with constipation-predominant irritable bowel syndrome (IBS) receiving oral tegaserod 2mg twice daily for 1 week compared with those receiving placebo. In addition, there was a mean 20% increase of proximal colonic emptying in these patients. ▴ Oral tegaserod 2 (p < 0.05) or 6mg twice daily improved symptoms of abdominal discomfort, bloating and constipation (assessed using a Subjects’ Global Assessment Scale) compared with placebo in patients with constipation-predominant IBS in a double-blind, dose-ranging study. ▴ The most frequent adverse events in patients with constipation-predominant IBS receiving oral tegaserod were transient diarrhoea and flatulence. ▴ No clinically relevant changes in blood pressure, pulse rate, QRS or QT_c interval were reported with tegaserod doses of 25 to 100mg.