A comparison of the effect of loperamide in oral or suppository form vs placebo in patients with ileo-anal pouches

Objective. The effect of the anti-diarrhoeal drug, loperamide hydrochloride, on bowel function in patients with an ileo-anal pouch was studied by means of a blinded, three-tailed, case-controlled and randomized crossover trial, using a daily dose of 12 mg in either oral (4 mg t.d.s.) or suppository (6 mg b.d.) form. Patients and methods. Daily stool frequency was recorded in a diary and an objective measure of pouch motor function was obtained at the end of each treatment phase. Ten subjects (seven males, three females) aged 23-50 years (median 38 years) were studied 9-48 months (median 27 months) after ileostomy closure. Eight pouches had been constructed for ulcerative colitis and two for familial adenomatous polyposis (9J, 1W). Results. Mean daily stool frequency during the oral loperamide phase was lower than during both the placebo (P = 0.05) and suppository (P < 0.02) phases. Stool frequency did not differ significantly between placebo and suppository phases. There was a strong inverse correlation between mean daily stool frequency and pouch capacity (r = -0.82 after both oral and suppository phases). Large isolated pouch contractions were evident in five of eight subjects studied; suppression was observed in two of the five after oral loperamide and in three of the five after loperamide suppositories. Rhythmic pouch contractions were seen in four subjects and suppression was evident after loperamide suppositories (but not after oral loperamide) in three. A daily oral dose of 12 mg loperamide significantly lowered stool frequency in pouch patients and modified some aspects of pouch contraction. Loperamide suppositories produced more prominent suppression of pouch contractions but did not lower stool frequency. Conclusion. This suggests that the beneficial effect of oral loperamide is primarily due to its action on intestine proximal to the pouch itself.