Pyrethrins & Pyrethroids
Pyrethrins & Pyrethroids
insecticides
Alternate names
pyrethroids, Chrysanthemum, flea and tick topical spot-on medications, bifenthrin, permethrin, allethrin, tetramethrin, cyfluthrin, cyhalothrin, cypermethrin, deltamethrin
Toxicity to pets
Pyrethrins are a class of drugs derived from the Chrysanthemum flower/plant, while pyrethroids are synthetic derivatives. Pyrethrins and pyrethroids typically come in varying concentrations (from < 1% to up to 55% or more). Higher concentrations can be safely used on dogs; however, cats are very sensitive to these chemicals and cannot metabolize these drugs well as dogs. One of the most common ways we see cats being poisoned by pyrethrins is by inappropriate application of dog flea and tick medications placed on a cat; this should never be done without consultation with a veterinarian. Less commonly, cats may be poisoned by licking or grooming a flea and tick medication off a dog that had recent topical spot-on application.
In cats, signs of poisoning include profuse drooling, vomiting, tremoring, hyperexcitability, agitation, seizures, weakness, and difficulty breathing. Untreated, it can be fatal. These signs are rarely seen in dogs. In dogs, signs of parasthesia (a tingling sensation), scratching, drooling, etc. may be seen. Treatment includes prompt removal of the product (by bathing with a liquid dish soap like Dawn, Joy, Palmolive) to get the greasy substance off.
If you think your dog or cat are having side-effects or were exposed to pyrethrins/pyrethroids, call your veterinarian or Pet Poison Helpline immediately for life-saving treatment advice.
Dogs
Toxicity Level
Cats
Toxicity Level
Disclaimer
The content of this page is not veterinary advice. A number of factors (amount of substance ingested, size of the animal, allergies, etc.) determine what is toxic to a particular pet. If you think your pet has eaten something potentially toxic, call Pet Poison Helpline or seek immediate veterinary treatment.