Effects of loperamide on ileoanal pouch function

Abstract

Background: Opioid analogues are used to manage increased bowel frequency in patients with an ileoanal reservoir. The aim of the study was to determine the clinical efficacy of loperamide in patients with an ileoanal reservoir and to assess its effect on pouch motility.

Methods: Fourteen patients with a pouch who had normal pouch emptying and anal function were studied. Ambulatory pouch and anal motility, and stool weights, were recorded for 24 h while taking no medication and for 24 h while receiving 8 mg loperamide. In a second analysis, patients were divided on the basis of bowel frequency into those with 4 or fewer motions (good function; n=6) and those with more than 6 per day (poor function; n=8), to determine any differential effects of loperamide.

Results: Loperamide decreased median bowel frequency (no loperamide 5.5 versus loperamide 4.0, P=0.03) and 24-h stool weight (610 g versus 413 g, P=0.03) but not individual stool weights. Patients with poor function had both higher bowel frequency (8.0 versus 3.5 per 24 h, P=0.004) and higher stool weight (728 g versus 430 g, P=0.05) with no treatment than those with good function. High-amplitude pouch pressure waves were greater in number before defaecation in patients with poor function and did not decrease with loperamide, in contrast to patients with good function. Pouch baseline pressure decreased after defaecation to a similar extent in both groups and was not affected by loperamide.

Conclusion: Loperamide 8 mg per day reduces bowel frequency by reducing total stool weight, not individual stool weights. In patients with good function it also affects pouch motility. High bowel frequency is associated with increased pouch high-pressure waves.