Are Seresto Flea Collars Safe? It Depends On Who You Ask

Category: Cat Healthcare, Fleas
Reading Time: 4 minutes

Are you having some misgivings about that Seresto flea collar your cat is wearing? Despite thousands of incident reports to the Environmental protection Agency, both the EPA and toxicologists at the Pet Poison Helpline say not to worry. A recent review of the scientific literature on Seresto collars and their own animal poison control case data show the collars are safe, the toxicologists say. Maybe they are. But there are other safer natural ways to get rid of fleas, and your cats won’t have to breathe insecticide from the collars around their necks.

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Do Seresto Flea Collars Kill?

Are Seresto Flea Collars safe? They may be. But this cat is going to try natural flea control.

This cat is going to try natural remedies for fleas.

In March, USA Today published a shocking report by Johnathan Hettinger of the Midwest Center for Investigative Reporting. Using documents provided by the Center for Biological Diversity, a watchdog group that works to protect endangered species, Hettinger found that the Environmental Protection Agency has received at least 1,698 incident reports of related companion animal deaths since Bayer Animal Health introduced Seresto Flea and tick collars in 2012.

In all, Hettinger writes, the EPA has received more than 75,000 incident reports related to Seresto collars. Nearly 1,000 involved harm to humans.

Seresto collars release small amounts of imidacloprid and flumethrin, two pesticides that kill fleas and ticks but are said to be safe for cats and dogs. They work for about eight months.

The most common complaints to the EPA involve skin irritation, scabs on the skin, fur falling out, lethargy, seizures and loss of motor function. And the EPA isn’t the only one to hear bad things about Seresto flea collars. Reviewers on and Amazon also mention hair falling out and neurological issues that were resolved when the collars were removed. One cat went blind but regained her vision when her people took the collar off. 

Despite the thousands of incident reports, the EPA has yet to say a word about the safety of Seresto flea collars. And now, the toxicologists at the National Pet Poison Helpline have weighed in with their own opinion.

In a May statement, the Pet Poison Helpline suggested you can’t completely trust an article that appeared in just one newspaper.

“As with any medication for you or your pet, it is important to compare the potential risks of a treatment with the proven benefits,” the Poison Helpline toxicologists say.

“In the medical opinion of our boarded veterinary toxicology experts, these collars are a safe and important treatment for the vast majority of cats and dogs. The health protections these collars provide far outweigh the extremely rare risk of a serious adverse event.”

To reach their conclusions, the toxicologists looked at the scientific literature on Seresto collars and their own case data.

Since 2013, they say, the Poison Helpline has managed about 400 cases involving Seresto collars. Most were dogs who ate all or part of the collar.

About 50 percent of the Helpline’s patients were vomiting. Thirteen percent were lethargic. Nearly six percent had decreased appetite and diarrhea, and one percent were panting and agitated.

The most notable finding in our data,” the toxicologists write, “is the distinct lack of severe neurological signs such as tremors, severe ataxia, and seizures.” Also, they say, there were no reports of deaths.

Here’s something else to think about, too. Some of the complaints to the EPA may have nothing to do with Seresto collars at all. Manufacturers have to report every claim of an adverse reaction to the EPA or FDA, even if it’s unlikely the product caused the reaction.

On the other hand, there could be thousands of people who don’t report adverse reactions, either because they don’t know how or don’t want to take the time. 

Getting Fleas To Flee Naturally

No matter how you do it, it’s important to get your cat’s fleas to flee and prevent them in the first place. Fleas are nasty little buggers and can cause anemia, flea allergy dermatitis and tapeworms, in addition to making your cat itchy and miserable. If you’re like me and don’t want to put insecticides on your cat, here are some ways to prevent and get rid of fleas naturally. 

1. My favorite defense against fleas is food-grade diatomaceous earth. To get rid of fleas in your home, sprinkle it on your carpeting and upholstered furniture. Then vacuum it up. Also, put it on your cats’ bedding after you’ve washed the bedding in the hottest water possible.

To treat your cats, use a flea comb to comb it into their fur, keeping it away from their eyes and noses. You’ll have to do this every day until the fleas are gone because it kills live fleas but not unhatched eggs.

2. Using just a flea comb works, too. This is the one I have, and my cats love it. Put your cats on a folded sheet, so you can squish any fleas that escape the comb. Put the hair you comb off in a glass of soapy water and get rid of the water outside. Flushing cat hair down the toilet can cause serious clogs! You’ll have to do this often until the fleas are completely gone.

3. Other ways to repel fleas include adding 1/2 tsp of Brewer’s yeast to your cat’s wet food, comb your cat with a mixture of half apple cider vinegar and half water, or squeeze fresh lemons or oranges and rub the juice into the cats’ fur. Beware though: Many cats hate the smell of citrus. Put a bit on a leg before you do the whole cat.

Pet Age Magazine likes these products for cats.

4. Wondercide Flea and Tick Spray. Plant-based and made from essential oils, this product is safe for cats and kittens. I used it without much success, but maybe the fleas plaguing my poor old cat were especially hardy. And he didn’t like smelling like lemongrass.

5. Pet Naturals Flea+ Spray. This product is made from the essential oils of lemongrass, cinnamon and sesame and castor oil and gets good reviews on Amazon. Many cats are frightened by sprays though. I’d put it on a cotton ball or washcloth and rub it into the cat’s fur.

When you treat your cat, you’ll also need to treat your home. And there’s a good use for that Seresto Flea Collar. You can put it in your vacuum cleaner bag to kill any fleas you vacuum up.

What do you think? Would you use a Seresto Flea Collar? Tell us in the comments below. 

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