Veterinarian-written / veterinarian-approved articles for your cat.

This Common Product Could Kill Your Cat

Never use dog flea and tick products on a cat.

Did you know that fewer products, chemicals, and medications can be used on cats than on dogs? It's true: cats are extremely sensitive to many things that wouldn't be harmful to a dog or a person. Two examples of this are Tylenol and ibuprofen.

One other product that is linked to injuries and deaths in cats every year is spot-on flea and tick control that is labeled for dogs.

Don't Use This Product on Your Cat

Every year, cats are injured and some die when people use flea and tick spot-on products meant for dogs on them. This most commonly happens in three situations:

  • Someone doesn't read the packaging well enough or grabs the wrong package by mistake
  • An owner purposely uses a tiny amount of a dog product on their cat thinking that the reason it isn't for cats is because cats are smaller and don't need as much. That isn't the case. The problem is that the chemical used in many dog flea and tick products is toxic to cats.
  • A dog product is used on a dog, and then a cat rubs on or licks that dog shortly afterward.

Dog products shouldn't be used on cats. Feline systems are different than canine ones, and it's more than just a difference in size.

Permethrin Toxicity in Cats

Permethrin, a chemical used in many canine spot-on flea and tick preventatives, is extremely toxic to cats. Cats' livers can't break permethrin down effectively, so it becomes concentrated in the cat's body, especially in the nervous system.

Permethrin exposure in cats causes muscle tremors, drooling, anxious behavior, seizures, and death. Treatment must begin as soon as possible after exposure and includes the aggressive use of muscle relaxants, seizure control medications, and other supportive care.

How to Keep Your Cat Safe from Permethrin

Here are some ways to make sure your cat isn't exposed to a canine spot-on flea and tick product that could lead to toxicity and death:

  • Never use a dog spot-on product on a cat.
  • Never use any part, even one drop, of a dog spot-on product on a cat.
  • Separate cats from dogs that have had canine spot-on products applied to them until the product is completely dry.
  • Read all labels carefully before using them on your cat. Be aware that there are not always large, easy-to-read warnings on the packaging. If the product is for dogs, don't use it on your cat.
  • Don't use over-the-counter flea and tick products on your cat without checking with your veterinarian first.

If you think your cat might have been exposed to permethrin, do not delay. Call your veterinarian immediately and follow their instructions.

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