When shopping for flea and tick preventives, we cannot take a "one and done approach" for both our dogs and cats. Cats must never be given a product labeled for dogs.
Some dog-formulated topical products contain active ingredients that are safe for dogs but toxic to cats and small animals. Permethrin (a pyrethroid) and amitraz are two of these ingredients. Most other pyrethroids are not safe for cats or small animals either.
Topical flea and tick products are regulated by the Environmental Protection Agency (EPA). These products must use clear marking on the package to differentiate between dog and cat products. They must also clearly distinguish by pet weight. For instance, some brands have different formulas for kittens than for adult cats, and the amount of active ingredient usually differs in each formula. Always take the time to read the label, the package insert, and accompanying literature before applying a flea/tick preventive on your cat.
When using a topical flea and tick product, carefully follow label application directions and monitor your cat for any signs of an adverse reaction after application, particularly when using a product for the first time. If a dog product is mistakenly applied to a cat or small animal, contact a veterinarian immediately.