Randomized Trial of Mosapride Versus Placebo in the Treatment of Constipation-Predominant Irritable Bowel Syndrome

Inclusion Criteria: * Rome III Criteria for IBS: Patients must have recurrent abdominal pain or discomfort at least 3 days per month during the previous 3 months that is associated with 2 or more of the following: * Relieved by defecation * Onset associated with a change in stool frequency * Onset associated with a change in stool form or appearance In addition, patients have to experience at least two of the following symptoms for at least 25% of the time \[11\]: * Altered stool frequency (\< 3 bowel movements per week) * Altered stool form (lumpy/hard i.e. Bristol type I-III \[see appendix 1\]) * Altered stool passage (straining, urgency, or a feeling of incomplete evacuation) * Passage of mucus, bloating, or a feeling of abdominal distension Exclusion Criteria: * Previous allergy to mosapride * Nocturnal Symptoms (pain in the middle of the night, or other nocturnal symptoms which suggest an organic disease) * Age \< 18 years * History of bloody stools or melena * Diarrhea (\>3 bowel movements per day) * Constitutional symptoms (fever, weight loss) * Severe constipation (\< 1 bm/week) * Pregnancy or lactation * Patients with history of cardiac arrhythmias * QT prolongation on baseline ECG * Chronic laxative use and dependence * Patients with previous history of congenital heart disease * Patients with previous history of hypokalemia or hyperkalemia * Patients taking the following classes of drugs: HIV antivirals, macrolides, anti-arrhythmics, and azole drugs.