Influence of olsalazine on gastrointestinal transit in ulcerative colitis.

The effect of olsalazine on stool output and the transit of a solid radiolabelled meal through the stomach, small intestine and colon was studied in six patients with ulcerative colitis intolerant of sulphasalazine. Olsalazine 250 mg four times daily significantly accelerated gastric emptying (mean +/- SD; 45.3 +/- 24.2 min v 67.3 +/- 33.1 min, p less than 0.05), mouth to caecum transit time (242 +/- 41 min v 325 +/- 33 min, p less than 0.02) and whole gut transit time (60.5 +/- 26 h v 37.8 +/- 17.8 h, p less than 0.05). No significant changes were seen in mean daily stool weight (215 +/- 41 g v 162 +/- 62 g) and mean daily stool frequency (2.2 +/- 0.6 v 2.4 +/- 1.8). None of these patients developed diarrhoea, but acceleration of gastric and intestinal transit may be responsible for the diarrhoea reported in some patients taking this drug.