The effects of loperamide on continence problems and anorectal function in obese subjects taking orlistat.

Author(s): Fox M, Stutz B, Menne D, Fried M, Schwizer W, Thumshirn M

Affiliation(s): Department of Gastroenterology, St. Thomas' Hospital, London, UK. mark.fox@doctors.org.uk

Publication date & source: 2005-09, Dig Dis Sci., 50(9):1576-83.

Publication type: Clinical Trial; Randomized Controlled Trial

Continence problems during treatment with orlistat (a lipase inhibitor) are caused when susceptible patients are exposed to increased volumes of loose, fatty stool. Aim: To investigate the dose-response effects of loperamide on continence and anorectal function in subjects susceptible to continence problems on orlistat. METHOD: Ten obese subjects enterred a randomized controlled, double-blind study of loperamide at placebo, 2, 4, and 6 mg/day in a factorial design. Continence problems during orlistat treatment were self-assessed by patient diary. Anorectal function and continence were assessed by barostat, manometry, and retention testing. RESULTS: Loperamide increased stool consistency with dose (p = 0.07) and this effect reduced continence problems during orlistat treatment (p < 0.05). A bell-shaped dose-response relationship was present with anal sphincter function (p < 0.01) and anorectal sensitivity (p < 0.01). CONCLUSION: Loperamide has beneficial effects on stool consistency and continence in obese subjects taking orlistat. The effect on stool consistency appeared more important than effects on anorectal function.