Compositions and methods for killing ectoparasites on a subject. Compositions containing a fatty acid ester, e.g., isopropyl myristate, effective for killing ectoparasites is described. Also described are compositions containing a fatty acid ester and a siloxane (e.g. decacyclomethicone). The compositions can also contain a mectin and/or a mycin, and S-methoprene. The compositions are useful against a variety of ectoparasites that afflict humans, animals, and plants, e.g., head lice, fleas, body lice, crab lice, scabies, ticks, and plant parasites.
