Advocate Fleas, Heartworm & Worms for CatsAdvocate is a fast acting, water resistant, easy to apply monthly spot on offering comprehensive parasite protection. It kills fleas fast and on contact, so there's no need for them to bite. Reinfesting fleas stop biting in 3 5 minutes and are killed within 1 hour. Larval flea stages are killed in the cat's surroundings, and it reduces the incidence of flea allergy dermatitis. Advocate also treats and controls mange and ear mites. Advocate is a cat