If your cat has a significant number of fleas, treat both your cat and your home. Giving your cat a bath with flea shampoo is usually the first step. Most flea shampoos work well and kill adult fleas. Read the directions on the cat shampoo carefully. Flea shampoos usually don't offer residual protection, which means your cat has no protection against fleas once the bath is over.
Flea dips offer some residual protection.
They repel fleas for a certain amount of time after you dip your cat. However, since a flea dip remains on a cat's fur, the cat will ingest it when it grooms itself. Therefore, some veterinarians don't recommend flea-dipping for cats. Flea collars kill fleas on the cat's face and neck, but they don't kill all of the fleas on a cat's body. Some cats are allergic to flea collars and develop a rash or lose the fur on their necks.