Aqueous extract of antidiarrhoeal formulation (ADF) containing Holarrhena antidysentrica, Aegle marmelos and Punica granatum was investigated for antidiarrhoeal activity against charcoal-induced gut transit, serotonin-induced diarrhoea and $PGE_2-induced$ small intestine enteropooling in rats. The control, standard and test groups of experimental animals were administered with normal saline (p.o.), diphenoxylate hydrochloride (5 mg/kg, p.o.) and ADF (250 mg and 500 mg/kg, p.o.) respectively except the control group of $PGE_2-induced$ small intestine enteropooling which received only 5% ethanol in normal saline (i.p.). Charcoal (10 ml/kg, p.o.) and serotonin $(600;{mu}g/kg,;i.p.)$ were administered after 30 min, while $PGE_2;(100;{mu}g/kg,;p.o.)$ was administered immediately afterwards. The distance traveled by charcoal in small intestine was measured after 15 and 30 min of charcoal administration, diarrhoea was observed every 30 min for six hour after serotonin administration and the volume of intestinal fluid was measured after 30 min of $PGE_2$ administration. Oral administration of ADF significantly inhibited the frequency of defaecation and decreased the propulsion of charcoal meal through the gastrointestinal tract, reduced the wetness of faecal dropping in serotonin-induced diarrhoea and also reduced the $PGE_2-induced$small intestine enteropooling. ADF may have potential to reduce the diarrhoea in rats.