Frontline plus covers your pet’s whole body within 24 hours of application.frontline plus will get rid of all fleas within 18 hours of contact with your pet and will kill all ticks within 48 hours after coming in contact with your pet.frontline should work on the cat within 24 hours but if your still seeing them then maybe they are new ones that you cat has picked up and they should die off within the next. Flea combs help remove live fleas, although it doesn’t kill them. Lapcats Sacramento Area Cat Kitten Adoptions Cat Fleas Flea Treatment Cat Fleas Treatment Frontline is a liquid medication which contains the active ingredient fipronil, an insecticide, which is used to treat and prevent fleas, ticks and lice in dogs and cats. How does frontline work on cats . Through the process known as translocation, frontline is then gradually spread around your pet’s body for one month. I have always used it on my cats and dogs and loved it. The chemical stops the neurons in the insect's ...