Widespread insecticide resistance in head lice to the over-the-counter pediculocides in England, and the emergence of carbaryl resistance

The data suggest head lice resistance is present in many parts of England to over-the-counter products containing synthetic insecticides (permethrin, phenothrin and malathion). They further suggest that resistance is starting to develop to carbaryl in head lice in Leeds and that extensive use of this product would lead to significant resistance.