Zodiac Flea & Tick Spray for Dogs and Cats kills adult fleas and ticks fast. It also kills American dog and Brown dog ticks. The quickest way to kill a flea and tick is to expose them directly to a wet insecticide product. Zodiac Flea & Tick Spray is applied directly to your pet's coat, penetrating to the skin where fleas and ticks are usually found. One treatment controls adult fleas and ticks and prevents flea eggs from hatching for up to 2 months. Application once a month should be adequate given the residual control. For severe flea problems, treatments can be performed weekly.