If you are looking for a quick answer to this question, I might disappoint you by saying that none of these is better than the other. They are both effective flea treatments that work for most cats.
However, in my own personal experience, and while I was practicing, I will say that I was more likely to recommend Advantage II rather than Frontline.
Frontline vs. Advantage — The ingredients
There are different ingredients in these products, and that’s what I will start with.
Frontline for cats – Ingredients
Frontline contains fipronil, which works by effectively attacking the fleas’ nervous system (the brain and the spinal cord). Since they are basically paralyzed, the fleas end up dying as they become incapable of feeding.
Advantage II – Ingredients
Advantage II, on the other hand, contains a combination of two substances — imidacloprid and pyriproxyfen. This is the reason I’m more likely to recommend it to pet parents, and I’ll explain below.
Thanks to its ingredients, Advantage II is capable of both killing the fleas (using a somewhat similar process to what fipronil does, meaning that it affects the fleas’ nervous system), but it also attacks a variety of fleas (eggs, larvae, and adults).
This second capability comes from the second substance that Advantage II contains, pyriproxyfen, which acts as an insect growth regulator.
What I’d also like to add here is that there is another product made by the same company that manufacturers Advantage II and it goes by the name Advantage Multi. This one can kill both intestinal worms and heartworms, but it’s rarer in North America.
There is no difference when it comes to how you will apply either of these products because they’re both spot-on solutions.
It’s true that some pet parents say that one is better than the other, but that depends on whether they’re original or counterfeits or if they have been applied properly.
It can be a little challenging for some people to use spot-on solutions.
They can fail to pierce the top of the applicator properly, they might not move the cat’s fur out of the way so that they can apply most of the solution on the skin, the cat might move right then and there, leaving the pet parent to drop most of the insecticide on the floor… there are many variables.
It’s true that some folks say that they’re usually more capable of applying Frontline better than Advantage II, but I haven’t found this to be true while applying any of these two solutions in my practice.
What about the dosage?
Well, we do have a significant difference in this case.
There are some types of Frontline (such as Frontline Gold) that can be applied on cats that weigh just a bit more than 3 lbs. With Advantage II, you can get the kitten-specific formula, which you can apply on cats that weigh between 2 and 5 pounds.
However, if you’ve used Advantage II or trust it more for one reason or the other, you can always dosage it yourself. I know that vets don’t usually recommend this, but hear me out.
For example, you have two cats that weigh 4.5 lbs each. You can get a 9 lbs Advantage II dosage, use a syringe to get all of the insecticide out of the applicator container, and then half the solution so that you can apply it on both of your cats.
DO NOT try to apply half of the solution right from the applicator as it is opaque, and you have no control over how much you’re pouring on one cat or the other. Use a syringe or get the right commercial dose right off the bat.
Unless you get the incorrect dose of any of these two products, there’s nothing to worry about when it comes to safety. The ingredients are safe when they are applied to the right type of cat.
I have to mention that cats that are younger than 6 weeks of age should not be treated with any of these two spot-on solutions mostly because they probably have a lower weight than that for which Frontline and Advantage II are recommended.
Advantage II is recommended for cats that are at least 9 weeks of age, whereas Frontline is recommended to kittens that are at least 8 weeks of age. So, if you’re in a hurry, Frontline Plus might be the best option for you.
There are alternative ways of getting rid of fleas that a too young kitten might have — including by using a flea comb. On top of that, there are lots of natural sprays and wipes that you can use for the purpose. The important thing here is to keep the flea infestation to a minimum until you are allowed to use an actual insecticide.
Ratings and price
Advantage II seems to have become more popular over time, with it receiving more critical acclaim from cat guardians. The 4-dose option, for example, has over 5,000 reviews at some online marketplaces, and over 80% of them are 5-star ones.
Frontline Plus, on the other hand, is a 3.9-star product out of 5 based on the reviews it has gathered.
There is a significant difference when it comes to price. Since you will have to re-apply the flea product time and again until all the flea pupae are gone, you’re going to have to get several doses.
3 doses of Frontline Plus cost just under thirty bucks while 2 doses of Advantage II cost the same. You can get the larger container with 6 doses of Advantage II, meaning you’ll have enough for 6 months (usually under sixty at most online retailers).
In the end…
In the end, I still trust Bayer more, so I would go with Advantage II. I’ve worked with both while I was practicing, and I can’t say that one is better than the other, but I can say that the likelihood of you purchasing a Frontline counterfeit is much higher.
Plus, you have to consider that it’s a good idea to mix it up once in a while. Fleas tend to become resistant to some types of substances over time. You could use Advantage II for 3 months, then switch to Frontline for the next 3 and so on.
NEVER use flea products made for dogs on cats! Cats are extremely sensitive to some insecticides, including permethrin, which can be found in many dog flea products. Therefore, avoid using Frontline for Dogs or Advantix on a cat.
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