Assessment of the activities of Chasmanthera dependens Hochst. combined with other plants on chloroquine-sensitive and chloroquine-resistant Plasmodium berghei

•The study justified the ethnomedicinal antimalarial use of the combination of Chasmanthera dependens and Vernonia amygdalina roots.•A beneficial additive interaction was observed between Chasmanthera dependens and chloroquine.•The activity of C. dependens root on chloroquine-resistant Plasmodium strain in mice reported for the first time.