Kill fleas on cats at home by bathing your cat with citrus-based shampoos or lavender-, cedar- or eucalyptus-scented soaps. Groom the cat with a flea comb to work the parasites out from the skin.
When using a flea comb on a cat, pay special attention to the armpits and groin of the animal, areas where fleas can hide. Occasionally shake the fleas from the comb into a bowl of soapy water so that they drown. After grooming the cat, launder the cat's bed and disinfect the home. This prevents flea eggs from hatching and re-infesting the cat. For outside cats, sprinkle the lawn with cedar or diatomaceous dirt to help repel fleas. Certain plants, such as fennel, lavender, eucalyptus and marigold, also act as flea repellents.
Often the best way to eliminate a pest is to practice prevention tactics. Limit an inside cat's exposure to the outdoors. Regularly clean and vacuum your house to remove fleas and flea eggs. Salt, if sprinkled on the carpet, dries out and kills pests that have burrowed low enough to avoid the vacuum. Make sure your cat has a healthy diet rich in omega-3 fatty acids so that if it is exposed to fleas, its skin remains healthy.