Why Can't I Put Dog Flea Medication on My Cat?

cat with fleas

Cats and dogs have different sensitivities to medicine. As a result, veterinarians formulate different medications separately for not only dogs and cats, but different types and sizes of dog and cat.

Active Ingredient

Permethrin, the active ingredient in dog flea medication, acts as a poison for cats as well as fleas.

Metabolism

The metabolism of dogs break down permethrin differently than cats, allowing dogs to pass the synthetic insecticide through their urine. The metabolism of a cat cannot break down permethrin and it can quickly build to toxic levels.

Symptoms

Cats experiencing poisoning by permethrin may drool abnormally, vomit, or show signs of fatigue, muscle tremors, or even seizures.

What to do

Permethrin toxicity can lead to death. Seek veterinary treatment immediately if you suspect a cat may have been treated with flea medication intended for dogs.

Treatment

Veterinarians treat cats suffering from permethrin poisoning by thoroughly bathing the cat to remove all traces of flea medication. Fluids and medications to control seizures may also be used. Muscle tremors can last for several days, but most cats under veterinary care recover within a few days.

References

• Cat World: Pyrethrin and Pyrethroid Poisoning in Cats: Causes, Symptoms, and Treatment
• Advantix Info: Questions and Answers
• Permethin and Pyrethrin Toxicity in Cats

Resources

• Flea Control Guide