When you first notice your pet has fleas, bathing it with a flea and tick shampoo is the first step towards treating fleas and also for immediate relief. This will kill adult fleas fast, while cleansing the coat and removing flea feces. However, once the lather is rinsed off, it will no longer kill new adult fleas that jump onto your pet. If you are interested in long-term protection, we recommend you use the topicals, such as Frontline for dogs or cats, and Advantage for dogs or cats, or collars. These products provide long term protection against adult fleas that your pet might get. Once you have your pet on one of these products, it is not necessary to shampoo your pet as often as before.