Seresto Flea Collar Review: Do They Really Work?

Seresto Flea Collar Review: Do They Really Work?

Yikes! My dog has fleas!

Fleas and dogs go together like peanut butter and jelly, just much less appetizing.

This external pest has been around since the Jurassic Period!

It was most likely causing some itchy problems on our long-lost dinosaur friends, too.

However, unlike millions of years ago, we now have solutions for controlling fleas. One of these is the flea collar.

In this post, we’ll be “scratching” the surface of the flea and one of the most popular brands of flea collars on the market today; the Seresto flea collar.

Plus, we’ll also take a look at the toxic chemicals that can find their way into those inferior flea collars that you will certainly want to avoid.

Seresto flea collars, do they really work?

The short answer is yes! You can purchase them from Amazon here.

Fun Flea Facts

Before we wage war on the flea, let’s get to know our enemy a little better with these fun flea facts.

Did you know…

  • The most common flea is the Ctenocephalides felis or the “cat flea” which can be found throughout Canada and the United States.
  • There are over 2,000 known species of the flea.
  • One female flea can produce approximately 2,000 eggs over the course of her 2 to 3-month lifespan.
  • A female flea needs a blood meal to lay her eggs and she can consume up to 15 times her own body weight on a daily basis.
  • The flea can jump 110 times its own length. This is comparable to the average person having the ability to jump over a 30-story building!
  • When the flea jumps it will accelerate 20 times faster than the space shuttle.

Now that we’ve covered some interesting facts on fleas let’s learn about the chemicals that kill them.

Image by: Jeremy Bronson

Toxic Chemicals to Avoid in Flea Collars

There are four stages of a flea; the egg, the larvae, the pupae and the adult.

Flea treatments kill any one or all of the stages of the flea’s life cycle. For this reason, manufacturers choose very specific chemicals.

However, some chemicals prove toxic to both pets and humans.

According to the Pesticide Research Institute, we should avoid the following toxic chemicals that can be found in some brands of flea collars.


Amitraz is a chemical for use in both spot-on treatments and flea collars. This chemical is a possible carcinogen and can affect the endocrine system of pets such as the ovaries, testes and several glands.

Chemicals in The Carbamates Family (Propoxur, Fenoxycarb, Carbaryl)

Found in flea collars, dust, dips, and sprays, these chemicals are toxic to the nervous system of pets, people, and bees. All three of these chemicals are considered to be possible carcinogens.

In addition, the residue left on the pet’s fur from collars containing Propoxur pose a particular risk to children and animals.

Organophosphates (Tetrachlorvinphos (TCVP))

Commonly found in flea collars, sprays, and powders, this chemical is highly suspected to be a carcinogen, and can be toxic to the nervous and endocrine systems of pets and people.

These are the most common toxic chemicals you should avoid in your dog’s collar. Now let’s cover some safe and effective options to get rid of those pesky fleas.

Seresto Flea Collar- Safe and Effective

Manufactured by the Bayer brand, the dog collar uses two active ingredients that work in combination with each other to deliver protection against both fleas and ticks for up to 8 months.

The two active pesticides in the Seresto flea collar are.

Image by: Bad Apple Photography

Imidacloprid (10%)

This chemical mimics nicotine, the same one found in tobacco, and is highly toxic to sucking insects.

It’s a common ingredient in over 400 pets, garden, and home products. You can purchase it in powder, liquids, granules and even packets that dissolve in water.

How does Imidacloprid work?

Once the insect has ingested this chemical it goes to work to shut down the nervous system by stopping the individual nerves from sending signals.

This chemical is highly toxic to insects because it binds much better to the receptors of the flea’s nerve cells than it does to mammals or birds.

In flea collars, it works against both the larvae and adult stages of the flea and even lice.

The other good news is according to the EPA (Environmental Protection Agency) there has been no evidence in their tests that suggest Imidacloprid is a carcinogen.

Flumethrin (4.5%)

The second active ingredient in the collar is Flumethrin which works to kill and repel ticks in the nymph, larvae, and adult stages by shutting down the central nervous system of the parasite.

Even though it does belong to the α-cyano-pyrethroids family (a pesticide) the low dose found in the flea collar doesn’t pose a risk to either dogs, cats or people.

You can purchase the Seresto Collar here.

How Does The Seresto Flea Collar Work?

The partnership of the two active ingredients forms a synergistic action stored inside the innovative “polymer matrix” of the flea collar. The middle layer of the collar contains the highest concentration of the two ingredients.

As the molecules move towards the surface of the flea collar, their concentration levels lower to form a microlayer. The ingredients then release onto your dog after their hair/skin makes contact with the microlayer, spreading the treatment over your dog’s entire body.

This gives your dog immediate protection from fleas and ticks within 48 hours.

Of course, as with any chemical, the effects will eventually wear off. This is why the Seresto flea collar slowly releases the chemical properties to supply your dog with continued protection against these biting pests for up to 8 months.

It is also water resistant, so it will continue to work even when your dog goes swimming or is out in the rain.

This highly innovative and the safe flea collar has been taking the flea treatment market by storm. It’s currently leading the pack for safe, effective flea and tick protection.

Flea Collars and Your Dog

The best way to combat a flea problem is to prevent it from ever happening.

This is where the Seresto flea collar comes in handy. The product is your first line of defense against these nasty pests. It gives your dog up to 8 months protection, and you can use it in conjunction with other flea treatments like pills.

However, if you have any concerns about flea treatments and your individual dog, don’t hesitate to seek veterinarian advice.

You can read more reviews about the collar on Amazon here.

Thanks for reading and good luck fighting those pesky pests!


Your dog deserves the best

Subscribe to our newsletter and get the latest posts straight to your inbox!

Feature image by: Wonderlane