kills fleas on pet cats fast. One Advantage treatment will provide at least one month flea control on cats. Advantage flea control for cats is water-resistant, so it kills fleas even after shampooing and exposure to rain. Advantage medicine is applied to the back of the neck on cats. It can be used on adult cats and kittens 8 weeks old. It's available in 4, 6, and 12 month supplies for all sizes of cats. This flea treatment breaks the flea life cycle by killing flea larvae. Advantage kills 98% of fleas within 12 hours and continues to work for up to one month per application. Also, it is safe for use on pregnant and nursing cats. Give your cat the advantage of protection with Advantage Flea Control!