The effect of loperamide on bowel habits and anal sphincter function in patients with ileoanal anastomosis

Abstract

The effect of loperamide on stool frequency, volume, and weight and on the function of the internal (IAS) and the external (EAS) anal sphincter was investigated in 19 patients with straight ileoanal anastomosis. Nine patients had intact anal sphincter function (group I), and in the other 10 the function of the anal sphincters was impaired (group II). After 72 h without any medication, the patients were investigated on a standard diet on 2 consecutive days: the 1st day with placebo, and the 2nd day with loperamide (16 mg). Stool collection and anal sphincter manometry/electromyography (EMG) were done on both days. The median number of stools was reduced from 10 and 13.5 to 6 and 7 per 24 h (p less than 0.01), and the fecal weight reduced from 600 and 900 g to 400 and 500 g (p less than 0.01) from the placebo day to the loperamide day in groups I and II, respectively. The tone of the IAS was significantly increased by loperamide in group I but remained unchanged in group II patients. The EAS function, determined by EMG and pressure measurements, was not significantly changed in any group by loperamide.