Artemether is an artemisinin derivative that is artemisinin in which the lactone has been converted to the corresponding lactol methyl ether. It is used in combination with lumefantrine as an antimalarial for the treatment of multi-drug resistant strains of falciparum malaria. It has a role as an antimalarial. It is a sesquiterpenoid, a cyclic acetal, an organic peroxide, an artemisinin derivative and a semisynthetic derivative.