Head lice affect more than 100 million people worldwide annually. Permethrin (1% formulation) is efficacious but resistance is emerging. Malathion (0.5% formulation) is an alternative, but ...

and controls flea infestations but also kills chewing lice. The topical medicine protects for 30 days with one application, and fleas do not have to bite your cat for it to work — they die on ...