Effects of oral cisapride on small bowel motility in irritable bowel syndrome

Background: Cisapride has been reported to improve symptoms in patients with constipation-predominant irritable bowel syndrome. Aim: To compare the effects of a 24-h oral dose regimen of cisapride on interdigestive and post-prandial small bowel motor activity in irritable bowel syndrome patients with predominant constipation, irritable bowel syndrome patients with predominant diarrhoea and healthy subjects. Methods: In 12 irritable bowel syndrome patients (11 females, aged 44 ± 12 years) - constipation predominant (irritable bowel syndrome-C, n = 5) and diarrhoea-predominant (irritable bowel syndrome-D, n = 7) - and six healthy subjects, small bowel motor activity was continuously recorded using an ambulatory technique over a 48-h period. Subjects received, in single-blind fashion, placebo tablets q.d.s. in the first 24 h then cisapride 10 mg q.d.s. in the second 24 h. Additional control groups were 13 healthy subjects (eight females, aged 39 ± 13 years) and 10 irritable bowel syndrome patients (10 females, aged 49 ± 14 years) who were studied in identical fashion but who did not receive cisapride. Results: Cisapride increased migrating motor complex phase 2 motility index in both irritable bowel syndrome-D (P < 0.01) and irritable bowel syndrome-C (P < 0.05) patients, as well as in healthy subjects (P < 0.01). An increase in fasting discrete clustered contractions occurred in irritable bowel syndrome-D patients (P < 0.001) and in healthy subjects (P < 0.01), but not in irritable bowel syndrome-C patients; the proportion of discrete clustered contractions that were propagated, however, increased only in irritable bowel syndrome-D) patients (P < 0.001). In addition, cisapride resulted in an increase in post-prandial motility index in irritable bowel syndrome patients (P < 0.05). Such motor alterations were not observed during the 48-h recording period in the healthy or irritable bowel syndrome patient control groups who did not receive cisapride. Conclusions: Oral cisapride influences interdigestive and post-prandial small bowel motor activity in both irritable bowel syndrome patients and healthy subjects; the effects of cisapride may be more marked in patients with predominant diarrhoea than in patients with predominant constipation.