Permethrin is a pyrethroid insecticide. Pyrethroids are synthetic compounds made to mimic the pyrethrins that are isolated from chrysanthemum flowers. It is a broad-spectrum insecticide that works by interfering with a nerve cell's ability to send a normal signal by jamming open tiny gates on the cell that need to open and close rapidly to carry the message. Permethrin is used in agriculture, in public health mosquito control, and in residential settings. Products containing permethrin are also used on pets and on clothing.
Products containing permethrin may be liquids, powders, dusts, aerosol solutions, sprays, and treated clothing. Permethrin is used in cattle ear tags and flea collars, or in spot-on treatments for dogs. There are currently more than 1400 registered products containing permethrin. Some products are used to treat scabies and head lice on people.
Permethrin can affect insects if they eat it or touch it. Permethrin affects the nervous system in insects, causing muscle spasms, paralysis and death. Permethrin is more toxic to insects than it is to people and dogs. This is because insects can't break it down as quickly as people and dogs. Cats are more sensitive to permethrin than dogs or people because it takes their bodies a long time to break it down.
