Effects of oral magnesium sulphate on colonic motility in patients with the irritable bowel syndrome

Abstract

Magnesium sulphate, a substance known to cause release of cholecystokinin (CCK) from the small intestinal mucosa, was given by mouth (dose 0·1g/kg in 150 ml water) to 20 patients with the irritable bowel syndrome. A rapid increase in colonic segmental motor activity (onset within two to six minutes in most cases) was seen (percentage activity increased from 16·2 to 23·7 p2O, NS; motility index from 144 to 259, p2O, p<0·05; 135 to 350, p<0·05), and after the magnesium sulphate three of these patients experienced an attack of their usual pain. These findings provide further evidence that `functional' abdominal pain after food may in some cases be related to an exaggerated intestinal motor response to cholecystokinin.