An ectoparasiticide is an antiparasitic drug used in the treatment of ectoparasitic infestations.

An ectoparasitic infestation is a parasitic disease caused by organisms that live primarily on the surface of the host.

Medically, the term infestation is often reserved only for external ectoparasitic infestations while the term infection refers to internal endoparasitic conditions.

An external ectoparasitic infestation is a condition in which organisms live primarily on the surface of the host (though Porocephaliasis can penetrate viscerally) and includes those involving mites, ticks, and head lice.