is permethrin toxic to cats when dry

While permethrin and pyrethrin are safe for many animals, including dogs, it is highly poisonous to cats. The reason cats are sensitive to these compounds is that they are unable to break down these toxins as they lack the liver enzyme to do so. Instead, the chemical builds up in their bodies causing serious illness.

How are cats poisoned by permethrin?

When owners accidentally apply dog flea products to their cats, it is the most common way that cats become poisoned. They might believe that the dog product is just the chemical in a larger volume and that their cat will be okay if they apply a small amount. Regretfully, this is untrue, and even very small dosages of permethrin can cause severe illness in cats.

Cats can also be exposed to permethrin by interacting with dogs that have recently received a permethrin spot-on treatment. The cat may become poisoned if it grooms the dog, rubs against it, or just sits on the same furniture as the dog because the permethrin will remain on the dog’s skin and coat for a while.

We chose to investigate this a little more because we definitely didn’t want any cat tragedies. Heres what we found.

“Dont put the dog product on the cat,” says Dr. Lisa Murphy, associate professor of toxicology at the University of Pennsylvania School of Veterinary Medicine. She agrees that the most dangerous scenario for cats is an accidental exposure to a highly concentrated product meant for dogs.

It didnt take long for emails to come flooding in. Most were from concerned cat owners.

According to her, the largest issue for cats is when they come into contact with highly concentrated permethrin products intended for canine use. These products may be 45 percent permethrin or higher.

Murphy states that “the prognosis for a full recovery is excellent” even in the event that there are no complications.

Why is permethrin toxic to cats but not dogs?

The adage “cats are not small dogs” is frequently used, and it is accurate in regards to how cats’ bodies process certain substances and medications. Since the liver of cats lacks some proteins (enzymes) needed to convert some chemicals into safe forms, these chemicals can build up in the body and lead to serious illness. Because of this variation in drug metabolism, we should never presume that a product or medication that is safe for dogs will also be safe for cats to use.


Can cats be around permethrin after it dries?

Never spray around cats. Keep your feline friends away from the area while you’re treating your clothes because permethrin is highly toxic to cats. According to Sawyer, which makes permethrin products, treated clothing is not dangerous to cats once it has dried.

Is permethrin safe once dried?

Dry permethrin on treated clothing should not cause any problems for humans and most wildlife, though. According to the University of Rhode Island’s Tick Encounter Resource Center (TERC), a person who weighs 140 lbs. would experience no negative effects if he or she were exposed to 32 grams of permethrin per day.

What level of permethrin is toxic to cats?

“It’s the dose that makes the poison,” says Dr. Charlotte Means, director of toxicology at the ASPCA Animal Poison Control Center. The biggest problem for cats is when they are exposed to highly concentrated permethrin products meant for use in dogs, she says. These products may be 45 percent permethrin or higher.

Are permethrin treated clothes safe around cats?

Second, never spray when you are wearing the clothing you want to treat; clothing must be sprayed and then allowed to dry completely before you wear it. Permethrin should also never be sprayed around cats, for whom it is highly toxic.