How do you keep cats safe around permethrin?
Permethrin and cats
Permethrin products are a powerful tool to reduce tick and insect bites on people and dogs, but they aren’t equally safe for all members of the family. The decision to use permethrin products should consider all animals in close contact with the dog being treated.
Permethrin is in the pyrethroid family of pesticides, a group of organic compounds that are produced to mimic the effects of naturally-occurring pyrethrins found in Chrysanthemum flowers. It is considered very low-risk for humans and dogs, especially once it dries.
Cats have a much higher sensitivity to permethrin than humans or dogs do. At high concentrations, permethrin can poison cats, causing seizures, tremors, and other health effects.
The main sources of permethrin poisoning in cats are:
1. Improper use of a flea/tick repellent intended only for dogs. Permethrin products for dogs may contain 44% or higher concentrations of permethrin (nearly 90x the strength of the permethrin sprays formulated for use on clothing).
2. Accidental exposure to high-concentration dog products (e.g. the cat grooms a dog after has been applied to the dog’s fur or the cat and dog sit together or have close contact after application, transferring permethrin to the cat).
Recognizing permethrin poisoning in cats
Knowing the signs of permethrin toxicosis in cats is extremely important if you use any permethrin products in your household or on your other pets. Symptoms most seen in cats are related to the central nervous system. Seizures, muscle fasciculations, tremors, shaking, and ataxia are common signs of permethrin poisoning. Less common symptoms are emesis, ptyalism, anorexia, collapse, diarrhea, confusion, hyperesthesia, lethargy, and temporary blindness. Cats can also die from exposure to high concentrations of permethrin. Additionally, the onset of symptoms of permethrin toxicosis in cats is usually within a few hours of exposure. However, delayed symptoms have been observed up to 72 hours after exposure. Note that early intervention is important as either recovery or death typically occurs within 24 to 72 hours.
Treatment of permethrin poisoning in cats
Early treatment after permethrin exposure is important in prognosis. Treatment consists of controlling tremors and/or seizures, supportive care and removing any remaining permethrin. Also, fluids are administered to adjust hydration and to support kidneys function and blood pressure, and to help remove the toxins from their blood. Temperature is monitored in order to identify hyperthermia and/or hypothermia. The cat is often washed in shampoo or mild dishwashing soap. The prognosis is generally good given the cat receives prompt veterinary care. Treatment can last between 24-72 hours and cats that recover often do so within 48-72 hours.
How to keep your cat (and yourself) safe around permethrin
Never use dog tick preventatives on a cat. Talk to your veterinarian about appropriate tick preventatives for cats. Some cat preventatives do have a small amount of permethrin. Make sure you are using these formulations as instructed.
If you have a dog that is using permethrin products, keep animals separated until the dog's treatment is completely dry. Be sure to keep all tick-prevention medication stored safely away from all pets.
Always check with your veterinarian before using a new product on your pets, and consider ALL pets in or near the household, not just the specific pet being treated..
If you are treating clothing or outdoor gear using permethrin spray:
Let the gear dry completely before wearing or handling it and keep it out of reach of cats until the gear dries completely. Gear should dry within a few hours, but our staff usually let gear dry overnight to be extra safe.
If you handle items before they are fully dry, wash your hands afterward.
Additional Reading
Malik R, Ward MP, Seavers A, et al. Permethrin Spot-On Intoxication of Cats: Literature Review and Survey of Veterinary Practitioners in Australia. Journal of Feline Medicine and Surgery. 2010;12(1):5-14. doi:10.1016/j.jfms.2009.12.002
