Pyrethrin/Pyrethroid Poisoning in Cats

By Renee Schmid, DVM, DABT, DABVT for Pet Poison Helpline; Ahna Brutlag, DVM, MS, DABT, DABVT; Heather Handley, DVM

Cat in the veterinary office, sitting quietly on its owner's lap.Pyrethrin insecticides are naturally derived from the chrysanthemum (“mum”) flower, and pyrethroids are the synthetic (artificial) versions of this chemical. Pyrethrins are rarely found in products we use on a day-to-day basis; however, pyrethroids are commonly found in products around the home for insect control. The formulations of these products vary in concentration, additional ingredients (synergists), and carriers. Some intended uses include:

  • Home and outdoor yard and garden insecticides (these typically come in liquids, sprays, granules, and foggers) 
  • Over-the-counter medicated flea shampoos
  • Topical flea and tick preventatives

How poisonous are these insecticides to dogs, cats, and other animals?

Whether or not a pyrethrin or pyrethroid product is toxic depends on the animal species involved, as well as the concentration, synergists, and carriers used in the product. The use of pyrethrins/pyrethroids is generally safe in dogs; however, cats and fish are very sensitive to these products.

Fish may die from even the smallest exposure, so be sure to cover aquarium tanks with something non-porous like plastic wrap or remove the tank from an area you will be treating with a product containing a pyrethrin or pyrethroid.

Cats are also very sensitive to pyrethrins and pyrethroids because they’re unable to metabolize (break down) these agents quickly and efficiently due to their peculiar liver metabolism. Life-threatening signs may be seen in cats with even a small exposure to products containing pyrethroids.

How do cats become exposed to pyrethrin/pyrethroid insecticides?

Unfortunately, the most common exposure is from owner error. Some cat owners mistakenly or purposely apply a dog flea and tick product (a high concentration pyrethrin/pyrethroid product) to their cats. Canine/dog topical flea and tick spot-on products containing pyrethrins or pyrethroids should never be used on a cat without consulting your veterinarian. Always double- and triple-check what you are applying to, or using around, your cat. Never apply a “small dog” flea and tick medication to a cat.

Cats can also be exposed under these other scenarios:

  • They live in close contact with a dog (e.g., grooming each other, sleeping next to each other) and the dog was recently treated with a high-concentration canine pyrethrin/pyrethroid flea and tick preventative. It is best to separate your dog and cat until the flea-tick product is completely dry.
  • Many flea and tick shampoos or collars contain low concentrations of pyrethrins/pyrethroids, so they should only be used as directed and kept in a closed, safe place away from cats. Flea and tick shampoos or collars specifically labeled for cats are safe to use.

How can I tell if my cat has pyrethrin/pyrethroid poisoning?

Signs of pyrethrin/pyrethroid toxicity in cats are serious and life-threatening. Any of the following signs warrant an immediate visit to the veterinarian for further treatment:

  • Excessive salivation/drooling
  • Agitation or restlessness
  • Vomiting
  • Hiding
  • Incoordination or difficulty jumping, standing or walking
  • Shaking
  • Twitching
  • Tremors
  • Seizures
  • Dyspnea (difficulty breathing)
  • Hypothermia or hyperthermia

Pyrethrin/pyrethroid toxicity can be fatal for cats if not treated immediately.

What should I do if my cat is showing these symptoms?

If you suspect that your cat is having a severe reaction to a pyrethrin or pyrethroid, bring your cat to your regular or emergency veterinarian immediately. If you’re not sure what you’re seeing, immediately call your veterinarian or Pet Poison Helpline, a 24/7 pet poison control center at 1-800-213-6680. The sooner you seek treatment, the better the prognosis and outcome for your pet.

How does my veterinarian diagnose pyrethrin/pyrethroid poisoning?

Your veterinarian will make a presumptive diagnosis if there is a known or possible history of exposure to a product containing a pyrethrin or pyrethroid, coupled with signs described above.

Is there an antidote for pyrethrin/pyrethroid poisoning in cats?

No, there is no antidote for pyrethrin or pyrethroid poisoning. However, quick and effective treatment with decontamination, monitoring, and supportive care help minimize the extent and severity of signs.

How does my veterinarian treat severe pyrethrin/pyrethroid poisoning?

Once your cat is stable (i.e., not showing severe clinical signs), your veterinarian may bathe your cat with liquid dish soap to remove any remaining product and prevent further exposure. If clinical signs have developed, treatment will be based on the symptoms and route of exposure (skin, ingested, etc.). In addition, your veterinarian’s team will carefully monitor the cat’s temperature for an elevated or lowered reading. In most cases, the team will monitor bloodwork as well, to make sure blood sugar and kidney function remain normal.

What is the prognosis for recovery if a cat has severe pyrethrin/pyrethroid poisoning?

If your veterinarian can provide prompt, early treatment, the prognosis is generally good if the cat does not develop further complications secondary to neurological signs. If the cat develops neurological signs that are uncontrolled or develops clotting problems or kidney failure secondary to severe seizures or hyperthermia, then the prognosis is typically poor.

How can I protect my cat from this poisoning?

With any poisoning, rapid diagnosis and treatment is imperative. It is less dangerous for your pet, and less expensive for you to treat early.

  • Be very careful with topical flea and tick preventatives that you apply to your cat. Only use cat products on cats. Remember, while dog preventatives are safe for dogs, they can be very dangerous to cats.
  • To prevent accidental exposure, read the directions for any product carefully before use.
  • Keep your cat separate from any dogs that have been treated for 12–24 hours. This time allows the product to dry thoroughly. When in doubt, you can put a t-shirt on your dog to prevent accidental exposure to your cat until the product is dried.
  • Be cautious about the number of different flea/tick products used on your pet. If you have a flea infestation, call your veterinarian about proper and safe treatment for your pets and your environment.
  • Use the appropriate flea and tick preventative for your cat’s weight range. Do not use part of a larger-sized dose, or multiple smaller-sized doses, as this may result in poisoning. When in doubt, bring your cat to the veterinarian for a weigh-in.
  • Store all pyrethrin or pyrethroid products safely and out of reach of your pets.
  • Never use an insecticide on a pet that is not intended to be used on animals. Even if the concentration of insecticide is low, the carriers or other components may be harmful to animals.
  • Keep your cat away from any areas, both indoor and outdoor, that have been treated with a pyrethrin or pyrethroid product until it has completely dried.

Pet Poison Helpline, an animal poison control center based out of Minneapolis, MN, is available 24/7 for pet owners and veterinary professionals that require assistance treating a potentially poisoned pet. The staff provides treatment advice for poisoning cases of all species, including dogs, cats, birds, small mammals, large animals, and exotic species. As the most cost-effective option for animal poison control care, Pet Poison Helpline’s per-incident fee includes follow-up consultations for the duration of the poison case. Pet Poison Helpline is available in North America by calling 800-213-6680. Additional information can be found online at

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