ABSTRACT
Maerua crassifolia Forssk. Leaf is used in African traditional medicine for management of gastrointestinal disorders. The anti-diarrhoeal activity of the methanol extract of Maerua crassifolia leaf was investigated in rats. The phytochemical screening was also carried out. The methanol extract of Maerua crassifolia leaf dose dependently decreased intestinal propulsion of charcoal meal in rats. Maerua crassifolia also exerted significant anti-enteropooling effect in rats. A profound anti-diarrhoea activity was observed when the extract was tested in diarrhoeic rats. The frequency of defecation as well as the wetness of the faecal droppings was significantly reduced. Furthermore, the leaf extract produced 100% inhibition of castor oil-induced diarrhoea in rats. Phytochemical screening revealed the presence of alkaloids, saponins, tannins, terpenoids, flavonoids, steroids, resins and cardiac glycosides. The oral LD50 obtained was greater than 5000 mg/kg in rats. The study showed that the methanol extract of Maerua crassifolia leaf possesses anti diarrhoeal activity and its action may be linked partly to direct inhibitory effect of the extract on the propulsive movement of the gastrointestinal tract smooth muscle.