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Flea Product Reactions in Cats


The following scenario happens more often during fleas season around spring through summer: a well intentioned cat owner purchases an over the counter flea product and shortly thereafter, they find their poor cat itching and scratching to the point of creating bleeding sores. Something apparently is not right, so concerned, the cat owners call their veterinarian or the number posted on the label of the box.

It is not unheard of cats getting poisoned by flea products. The flea product causing problems may be under the form of dips, sprays, shampoos, spot-on topicals, and collars. Many times cat owners may mistakenly purchase a product for dogs that is toxic to cats. For instance, most spot on flea products for dogs contain highly concentrated permethrin products( 45% or 65% permethrin in spot on products) which in cats can cause toxic reactions while many dogs may tolerate them quite well.

Some cats have been known to develop toxicosis even if the flea products intended for dogs were not applied on them directly. Cats living in the same quarters of dogs treated with flea products have been known of absorbing the products by grooming the dogs or getting in close contact with them. A typical example is Advantix used in dogs. Its labeling clearly states ''If the household has cats or other animals, separate from the treated dog for about an hour until the product is thoroughly dry''

However, in many other scenarios the cat just simply reacts to the over the counter flea poroduct. These are cheap products found at retialers like Walmart or your average grocery store.There are hundreds and hundreds of these types of reaction in cats and dogs reported at BioSpotVictims.Org

While itching and scratching in itself is not a life threatening event, there have been instances where cats had developed more severe reactions, sometimes even fatal. Symptoms generally arise within minutes or hours of application. In some delayed reactions cats may exhibit symptoms even after 24-72 hours. Following are some symptoms suggesting topical flea poisoning.

Symptoms of Topical Flea Poisoning in Cats


-Skin Reactions



-Loss of Appetite

-Incoordinated Gait

-Constricted Pupils




-Trouble Breathing

Treatment of Topical Flea Poisoning in Cats

Treatment of cats itching and scratching only, mainly consists of removing the product as much as possible. This is accomplished by removing flea collars if worn and in bathing the cat if a topical spot on product, dip or shampoo was used. The cat must be bathed in lukewarm water with a mild dish detergent such as Dawn dish detergent and then dried with a towel. Hot or cool water may actuallt intensify the reaction. Dish detergents are recommended because it effectively cuts through the grease and works well in removing the product. Dawn dish detergents is what is often used to remove pertoleum from birds found in maritime areas where there where recent oil spills.

In some cases, a second or third bath may be needed if the cat appears still in discomfort.

Cats exhibiting more serious signs require immediate veterinary intervention. In this case, seizures must be controlled by Methocarbomal medications sometimes in conjunction with other anti-seizure meds. Once the cat is conscious and the seizures are under control, the cat may be bathed to remove residual traces of the topical, fluids may be given intravenously and general supportive care is administered.

Prognosis depends on the amount of exposure, the siwftness with which veterinary treatment is seeked and the over all general condition of the cat. Most cats will recover within 24-72 hours of treatment.

Why Over the Counter Flea Products are not Recommended

Over the counter flea productions can be less expensive but unfortunately many have been associated with adverse and even severe, fatal reactions.They should be avoided althogther. The safest flea products are those prescribed by your veterinarian such as Frontline, Advantage and Revolution. Always read labels carefully. Never use on cats products labeled for dogs. Read instructions and dosages very carefully.

Disclaimer: this article is intended for educational purposes only. If you suspect your cat is having a reaction consult with your vet immediately or contact the National Animal Poison Control Center: (888) 426-4435


For Further Reading:

Safer Flea Products Many Vets Recommend


Adrienne Farricelli (author) on August 30, 2013:

Wow, so sorry your cat had to go through such an ordeal. I too wonder what the hack are products like this doing on the market with so many complains?

Bill on August 30, 2013:

I look over the ADVANTIX packaging by BAYER..trusted BAYER and I don't know why they don't have anything on the package of what happens if you use this on cats. Most ..not most..but a lot of people are going to think WHAT IS GOOD FOR THE DOG IS GOOD FOR THE CAT...RIGHT? What harm will a couple of drops do. Well YOU IDIOTS AT cat looked like one of those Syrian Children after they just got gassed by Assad. I am so angry. Sue..I did the same thing..IMMEDIATELY WASHED THE CAT..WARM WATER AND DISH SOAP. I didn't have the $300 or $400 for the emergency vet on hand. I cut the hair where i put the drops. I filled plastic tub..or bathtub with warm water and put the dish soap directly on the spot and I washed and I washed and washed. I dried and then I washed. No chance of my cat drowning..he was just flapping away like a motor boat...his poor little feet and head were shaking uncontrolably. I know my cat ingested quite a bit and I called the emergency vet and I found out where they were just in case. After I washed and dryed and washed and dryed and washed and dryed. The cat was still vibrating and I asked my wife if she needed any assistance. The cats eyes were clear. He was breathing okay..I laid down with him and just held him ...this is like 4 hours into the ordeal...midnight. I woke up and he was eating my ear and walking around without acting like he had sand stuck to his feet.

Here are the tells...

6 PM put drops on him. 8 PM saw where he licked area...10 PM when cat would walk it was like little vibrations on fee...11 PM..full I started panicking...looking on internet..actually no good youtube videos...except 1 but you could barely understand person...I read this post and a couple of others..saw where you WASH with DISH SOAP or DOVE soap and CUT HAIR OF APPLIED AREA.

Give him or her a couple good baths...warm water and just dip and scrub..dip and scrub. Then I had a syringe for later...I gave him Tuna water every couple of hours for liquids. I was wondering if Milk would do anything to counter the ingested. But BAYER you are getting away with MURDER for not putting warning labels on the package. If cats where humans..and this happened to human..BAYER would be no more...BAYER..German Company...most like they have many casualities of cats in their laboratories...probably some of Hitlers old scientist making this stuff up...SCREW U BAYER!!!!

sue on November 08, 2010:

I used Advantage over 9 pounds on my 8 year old healty male Oriental Shorthair cat. Within minutes of application he became disoriented, could not walk straight, looked and acted drugged, his voice was strange, & he became very dry in the mouth. He could not jump up on the scratching post without wobbling. I immediately called the emergency vet and asked if I should wash off the Advantage...I used shampoo for about 6 washings, dried the cat, gave him 100 cc subcutaneous fluids and hand fed him some moist cat food. He was disoriented and druggy for over an hour. HAD I NOT BEEN THERE WITH THE CAT AFTER I APPLIED THE ADVANTAGE HE COULD BE A DEAD STATISTIC.

KT pdx from Vancouver, WA, USA on June 17, 2009:

Excellent article. As a cat person and someone who's worked with pet products, I'm glad this information is finally getting out through all the different channels. From my perspective and research I've personally done (as well as testimonials from pet parents that I've personally talked with), NEVER use flea collars, Hartz brand anything, or Bio-Spot anything.

The only good use of a flea collar is to cut it up and put it in your vacuum bag so it kills the fleas that you suck up.

Gypsy Willow from Lake Tahoe Nevada USA , Wales UK and Taupo New Zealand on June 16, 2009:

Useful info. Thanks

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