Alosetron relieves pain and improves bowel function compared with mebeverine in female nonconstipated irritable bowel syndrome patients R. H. JONES 1 , G. HOLTMANN 2 , L. RODRIGO 3 , R. S. B. EHSANULLAH 4 , P. M. CROMPTON 5 , L. A. JACQUES 4 & J. G. MILLS 4 1 Department of General Practice, Guy's, King's and St Thomas' School of Medicine, London, UK, 2 Department of Internal Medicine, University Hospital of Essen, Germany, 3 Gastroenterology Service, Hospital Central de Asturias, Oviedo, Spain, 4 Gastroenterology Clinical Development, and 5 Clinical Statistics, Glaxo Wellcome Research and Development, Stockley Park, UK Accepted for publication 15 September 1999 INTRODUCTION Irritable bowel syndrome is one of the most common gastrointestinal disorders, 1, 2 and has substantial impact on patients' quality of life and medical resource use. 3, 4 Irritable bowel syndrome is reported to account for 20±50% of referrals to gastroenterologists. 5 Esti- mates of the prevalence of irritable bowel syndrome in the general population are as high as 20%, with a clear predominance in female patients. 6 The most recent report of the Committee on Functional Bowel Disorders (Rome II) describes irritable bowel syndrome as a group of functional bowel disorders in which abdominal discomfort or pain is associated with defaecation or a change in bowel habit, and with features of disordered defaecation. 7 Irritable bowel SUMMARY Background: Irritable bowel syndrome is one of the most common gastrointestinal disorders, yet no therapy convincingly controls the multiple symptoms of this syndrome. Aim: To compare the ef®cacy and tolerability of the new 5-HT 3 -receptor antagonist alosetron and the smooth muscle relaxant mebeverine in a double-blind, multi- centre, randomized trial. Methods: Six hundred and twenty-three nonconstipated females with irritable bowel syndrome were randomized to receive alosetron 1 mg twice daily (n  319) or mebeverine 135 mg three times daily (n  304) for 12 weeks, followed by a 4-week post-treatment period. The primary ef®cacy end-point was monthly responders for adequate relief of irritable bowel syndrome related abdominal pain and discomfort (de®ned as patients reporting adequate relief on at least 2 out of 4 weeks). Secondary end-points included assessments of bowel function, including urgency, stool frequency and stool consistency. Results: There were signi®cantly more responders in the alosetron group compared with mebeverine at months 2 and 3 (P < 0.01). Compared with me- beverine, the alosetron group experienced signi®cant decreases in proportion of days with urgency and mean stool frequency, and had ®rmer stools within 1 week of starting treatment. A similar proportion of patients reported adverse events in the two treatment groups. Conclusions: In nonconstipated female irritable bowel syndrome patients, alosetron is signi®cantly more effective than mebeverine in improving symptoms. Correspondence: Jane Mills, Gastroenterology Clinical Development Glaxo Wellcome Research and Development, Stockley Park West, Uxbridge, Middlesex, UB11 1BT, UK. E-mail: JGM0522@Glaxo.Wellcome.co.uk Aliment Pharmacol Ther 1999; 13: 1419±1427. Ó 1999 Blackwell Science Ltd 1419