The antidiarrheal action of bismuth subsalicylate in the mouse and the rat.

The antidiarrheal effectiveness of bismuth subsalicylate was determined in two species of laboratory animals. Doses of castor oil were, at first, found to accelerate significantly the movement of a charcoal test meal along the small intestine of the mouse and rat and also to increase both the fecal output (dry or wet weight) and the frequency of diarrhea in mice. Bismuth subsalicylate significantly prevented the enhancement of charcoal-meal transport induced by castor oil in both mice and rats. Increased fecal outut (dry or wet weight) and increased frequency of diarrhea in mice were also significantly reduced by bismuth subsalicylate in a dose-related fashion. The findings in these experiments lead to the definitive conclusion that bismuth subsalicylate exerts antidiarrheal activity in the mouse and in the rat and support its use in therapy of common clinical diarrheal states.