Permethrin/Pyrethrin Toxicity in Cats
The return of warm spring weather is welcome after the cold of winter. Unfortunately, people and animals are not the only ones who feel revived and invigorated by the changing seasons. Soon, insects like fleas, ticks and mosquitoes will be out to pester us again!
It is important to protect outdoor animals against insect pests, and in some cases it is a good idea to protect indoor cats against heartworm disease, or against fleas if you have a dog that goes outside. Please don’t hesitate to contact the office if you would like a suggestion about an appropriate product for your cat.
The point of this blog entry, however, is not what product you should be using, but what you should avoid. A recent editorial and article in the Journal of Feline Medicine and Surgery highlighted the dangers of using inappropriate flea control products on cats.
For many years, the most effective and widely available products against fleas contained chemicals called pyrethrins, which are derived from chrysanthemums, and their synthetic relatives, called permethrins. Many over-the-counter flea control products still contain these chemicals. Although they can be relatively safe and effective when used properly, some cats are extra-sensitive to these chemicals and can get sick even when they are given a “normal” dose. More cats are in danger if they are exposed to high concentrations of these chemicals. This most frequently happens when an owner purchases a dog product and puts it on a cat, even if only a small portion of the dose is applies. This can happen accidentally, when an owner doesn’t realize they have bought a dog flea product, or can happen when an owner is trying to save money by splitting a dog dose between several cats.
Symptoms of permethrin toxicity include drooling, vomiting or diarrhea, and tremors. Tremors can progress to full-blown seizures and this is the symptom that can rapidly become fatal if not promptly treated.
It is also worrisome that cat poisoning can even occur when an owner puts a dog product on the family dog and the cat snuggles up to or grooms the dog.
The best way to avoid toxicity is to purchase cat flea and tick preventatives directly from the veterinarian so that you know you are getting the correct, permethrin-free product. If you must purchase a product in the petstore or grocery store, we strongly recommend buying Frontline, which does not contain permethrins. It is more expensive than other over-the-counter products, but the lower risk of toxicity is well worth the money. Read labels carefully to make sure you are not buying a dog product by mistake. Finally, if you put a flea control product on your dog, keep the dog and cats separated for about 24 hours to make sure the cat is not exposed to medication on the dog.
If you realize that you have applied the incorrect product to your cat, immediate bathing in lukewarm water and dishwashing hand liquid will remove most of the product and will minimize the amount of drug absorbed through the skin. If your cat has licked the product off of itself or another animal, bathing will not be of benefit and your should call your veterinarian immediately.
Remember, it’s not worth saving a few bucks on a cheaper flea product at the risk of your cat’s life or an expensive emergency visit! Please call the office if you would like a recommendation for a safe, effective parasite preventative. Also, please remember that so-called “natural” flea repellents may sound attractive, but are not effective and can contain ingredients like citrus oils that are also poisonous to cats.
