Advantage is the fast way to a flea-free home. An easy-to-use spot-on, Advantage is applied monthly. Its super ingredient stops fleas biting within 3 to 5 minutes and kills both adult fleas and larvae within 20 minutes ? breaking the flea life cycle. Advantage works on contact so fleas don?t get need to bite to be killed. It?s safe for kittens of any age and is water-resistant*.