The methanol extract of E. angustifolia DC was screened for the presence of secondary metabolites and was earlier tested for the median lethal dose LD50 using Swiss albino mice to ascertain the in vivo acute toxicity and hence the practically safe dose to be used in a three model antimalarial investigation. The result of the phytochemical screening indicated the presence of alkaloids, terpenes, tannins, flavonoids, saponins and anthraquinones. The extract was found to be very toxic to the mice, which guided our choice for practically safe dose in the three models of the antimalarial evaluations. The result of the suppressive test showed a significant % suppression compared to the control with values of 57.92%, 66.62%, and 75.62% for the doses 100mg/kg, 150mg/kg, and 250mg/kg respectively. The result of the prophylactic (residual malaria infection) tests showed a significant level of inhibition compared to the control for the three doses. The curative (established malaria infection) tests also showed a significant level of parasite suppression compared to the control with % parasitemia of 0.13 ± 0.07, 0.12 ± 0.06, and 0.07 ± 0.04 for the doses 100, 150, a nd 250mg/kg respectively. The result justified the use of E. angustifolia DC as remedy to malaria infection by the traditional medicine practitioners in North-Eastern Nigeria.