RESUMEN
The leaf of Theobroma cacao L. is used in traditional medicine in Ghana for the treatment of malaria, yet, with no scientific evidence of its antimalarial property in animals. It was, therefore, studied to validate the antimalarial property in Plasmodium berghei-infected mice. Infected mice were treated with an aqueous extract of T. cacao leaf at different doses of 100, 200, and 400 mg/kg daily for four days. Parasitaemia was determined before treatment and 24 hours following the last dose of extract. The % reduction in parasitaemia and ED50 and ED90 of the extract were determined. Body weight, rectal temperature, and daily mortality of mice were also recorded. The extract had ED50 and ED90 of 242.20 ± 29.38 and 351.00 ± 29.52 mg/kg/day, respectively. Percentage parasitaemia suppression was significant for all doses. The extract at the maximum dose of 400 mg/kg body weight had the highest % parasitaemia suppression of 79.19%; mean survival time of 24.00 ± 2.19 days and median survival of 23 days; body weight increase of 3.82 ± 0.59; and the lowest body temperature reduction of 0.79 ± 0.11°C. T. cacao leaf extract showed an antimalarial property in P. berghei-infected mice. This reinforces the justification for the use of the plant material in treating malaria in Ghana.