Artesunate is used in the treatment of malaria. It is not used to prevent malaria or to treat severe malaria (where it has affected the brain, lungs or kidneys).Artesunate is an antiparasitic medication. It works by producing harmful chemicals (free radicals) within the malarial parasite, thereby killing it. The intravenous form is preferred to quinine for severe malaria. Often it is used as part of combination therapy, such as artesunate plus mefloquine.