DAS-77 is a traditional herbal preparation composed of the young callous bark of mango (Mangifera indica Linn., Anacardiaceae) and the dried root of pawpaw (Carica papaya Linn., Caricaceae). This phytomedicine is claimed to have beneficial effects in the treatment of gastrointestinal disorders, including diarrhoea. To investigate the antidiarrhoeal effect of DAS-77 using standard pharmacological models. Normal and castor oil-induced intestinal transit, and castor oil-induced diarrhoea tests wore carried out in mice while intestinal fluid accumulation and gastric emptying tests were carried out in rats. Acute toxicity test and preliminary phytochemical analysis were also conducted. The results obtained in this study revealed that DAS-77 had no significant inhibitory effect on normal intestinal transit, castor oil-induced diarrhoea, intestinal fluid accumulation and gastric emptying. However, the inhibitory effect of DAS-77 was significant (p<0.001) relative to control in the castor oil-induced intestinal transit test. Peak effect was produced at the dose of 100 mg/kg (p.o.). The effect of DAS-77 in this respect was reversed by pilocarpine and propranolol, but not by phenoxybenzamine. DAS-77 did not produce any mortality given p.o. up to 10 g/kg, indicating the relative safety of the preparation. The i.p. LD50 was estimated to be 1122 mg/kg. The remedy was found to contain saponins, tannins, phenols and alkaloids. Findings in this study suggest that DAS-77 possesses antidiarrhoeal activity due to the inhibition of intestinal motility possibly mediated by muscarinic and alpha adrenergic receptors.