How canine and feline flea treatments differ

How canine and feline flea treatments differ

All of the higher end flea treatment products for cats and dogs, such as Frontline, Effipro, Advantix and Advocate are sold in separate versions for dogs and cats, and for dogs, in different size options too.

If you do the maths in terms of the size of the pipette given for each product and the size of pet it is designed to treat, you will see that it is actually cheaper like for like to buy the products for a larger pet, in terms of how much of the product you actually receive for the money.

This naturally has led to owners of cats and smaller dogs windering if they cannot make a saving by buying a large dog pipette of the product, and measuring out a smaller dose for their smaller pet. At one point, many sellers on Ebay and other similar sites were advertising such products for smaller pets at a lower price than the average, tapping into this market.

They achieved this by selling a large pipette of the product accompanied by a dosage syringe and guidance on how to divide up a larger dosage to suit a smaller pet, before this procedure was stopped by Ebay itself due to concerns about the safety of altering the dosage outside of the manufacturer’s instructions.

Canine and feline flea treatments differ from each other in many core ways, and there is a good reason behind why they are sold specifically for dogs or cats only, and should not be used interchangeably. Even if you own a dog, it is very unwise to purchase a product that is designed for a larger dog and try to work out the dosage yourself, and even more inappropriate and even potentially harmful to use dog products on cats, and vice versa. In this article, we will look at the three core differences between feline and canine spot-on flea treatment products.


The active ingredient in treatments for dogs and cats are generally different, and even when the same ingredient is used in products for both species, how much of it is included within the solution will vary between dogs and cats too. Some products have proven more effective on dogs than cats and vice versa, and some products that are very effective for one species might actually be unsafe for another.

When it comes to dogs, an active ingredient called Permethrin is one of the most widely used ingredients, while for cats, the closely related Pyrethrin is usually the chemical of choice.

Permethrin is stronger than Pyrethrin, and so flea treatment products for dogs that contain Permethrin can be toxic to your cat, and the same goes for alternative active ingredients present in other products too.

Likewise, certain flea treatment products that are effective for cats are not safe for dogs, and so using one product to treat both species can cause serious problems.

Dosage levels

How much of the active ingredient in the product is needed to treat your pet’s fleas without harming your pet is calculated according to the weight of your pet as well as their species. Cats tend to fall within a fairly narrow weight range, whether the cat is large or small, and so generally products for cats only come in one size.

However, dogs can range from just a few lb in weight for toy dogs to around the weight of the average person for giant breeds, and so a significant amount of variation is required within the range of products available for them!

This is another reason why you should never attempt to divide up a pipette of a treatment product at home in order to treat a smaller pet than that for which the product was designed; even if you use a measuring syringe, the chances of getting things wrong is fairly high.

Environmental factors

Flea and tick treatment products are constantly reviewed by their manufacturers in order to ensure that they remain effective, as over time, fleas can develop an immunity to the active ingredient within the product, and in some areas, this will affect the flea population in its entirety, rendering some products almost useless.

Flea and tick treatment products too are different to each other in terms of what they are designed to target; some will kill adult fleas, some will act as a repellent, some will inhibit the parasite’s ability to reproduce, and some products tackle ticks; some achieve all of these things in one go!

Where your dog or cat lives and the lifestyle that they lead can also affect the type of product that is the best fit for them; for instance, a cat that lives indoors only, or that is not in contact with a lot of other cats will not need as strong or as frequent treatment as an outdoors cat, and how many dogs are around your area may affect your dog’s needs as well.

Developers of flea and tick products spend a lot of time and money on ensuring that their products are a perfect fit for the animal that they are designed to target, and they work to review this all the time; interfering with the dosage, using the wrong product or otherwise altering the application of the product can not only mean that it may be ineffective, but that you are risking your pet’s health as well.

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