RESUMO
BACKGROUND: Chromolaena odorata is a plant commonly used traditionally to treat ailments including diarrhoea in Nigeria. METHODS: The ethanol leaf extract of C. odorata was studied for its anti-diarrhoeal activity using electrolyte test and castor oil-induced diarrhoea rats' models. Acute toxicity effect of the extract was also evaluated. RESULTS: The extract showed a dose-dependent protection against castor oil-induced diarrhoea at the tested doses (200 and 400 mg/kg body weights). The protection offered by pretreatment with 400 mg/kg body weight of the ethanol leaf extract of C. odorata with regards to reductions in the incidences of faecal wetness and rate of defaecations were statistically comparable to that achieved with Lomotil, a known anti-diarrhoeic drug. The result of the electrolyte test showed that the extract pretreated groups had significantly (p<0.05) lower potassium and sodium ions in their intestinal fluid when compared with the diarrhoeic untreated controls. This is well tolerated. CONCLUSIONS: The results indicate that the ethanol leaf extract of C. odorata is safe and possesses anti-diarrhoeal activity with electrolyte reabsorption proposed as the possible mechanism of action.