advantix is toxic to cats. DO NOT USE ADVANTIX on your dogs if you have cats in the house. even if a cat LAYS down on the same PILLOW an advantix-treated dog was laying on, it can end up w/serious health problems.
Frontline is the best thing going right now for cats until the Vectra people come out with one. Vectra not only kills fleas and ticks but it alse REPELLS them so they don't even have to bite your animal in order for the insecticide to work. It also does something that none of the other products do; it repels mosquitos, so your animal has less of a chance of contracting heartwork disease as well.
Until Vectra makes one for cats (they claim they will come out with a product within the year), the animal hospitals at which I have been a veterinary technician all strongly recommend Frontline. It can be easily procured online, at your vet's office, or in a ny *****/petsmart w/a prescribing veterinarian.