When a flea is exposed to Advocate® (imidacloprid) on a treated pet, the compound is absorbed through the insect’s intersegmental membrane and leads to death of the insect. It has been shown to kill adult and larval fleas within 20 minutes of contact. It also stops fleas from feeding in 3-5 minutes. Fleas are not required to bite the animal to receive a lethal dose. Any new fleas that pets pick up on “walks”, or from visiting animals, will also be killed before they can lay eggs.