EFFECTS OF LOPERAMIDE OXIDE ON GASTROINTESTINAL TRANSIT-TIME AND ANORECTAL FUNCTION IN PATIENTS WITH CHRONIC DIARRHEA AND FECAL INCONTINENCE

Background: Loperamide improves anorectal function in patients with ch ronic diarrhoea. We wished to investigate whether the prodrug loperami de oxide has similar effects. Methods: Eleven patients with chronic di arrhoea and faecal incontinence participated in a randomized, placebo- controlled, double-blind, crossover study of the effects of loperamide oxide (4 mg twice daily for 1 week). Results: Loperamide oxide reduce d wet stool weight and improved the patients' ratings of symptoms. Mou th-to-caecum transit time was not altered, but whole-gut transit time was prolonged. There were limited effects on anorectal function, but t he mean minimum basal pressure mainly contributed by the internal anal sphincter (IAS) was increased, as was the mean volume infused before leakage occurred in the saline continence test. Conclusion: Loperamide oxide is effective in the treatment of diarrhoea with faecal incontin ence; normalization of colon transit time and an increase in the tone of the IAS seem to be the main determinants of efficacy.