Permethrin is a synthetic pyrethrin derivative acts as a neurotoxin by depolarizing the nerve cell membrane. Permethrin disrupts the sodium channel current by which membrane repolarization is regulated resulting in fatal paralysis of the nerves in the exoskeletal respiratory muscles of susceptible arthropods, including lice and mite. Permethrin is sold under brand names NIx and Elimite to treat pediculosis, scabies and demodicidosis.