What is the difference between Advantage and Advantage II?
The main differences between Advantage and Advantage II for cats is that the original Advantage formula did not kill all stages of the flea life cycle. The new formula in Advantage II also kills the flea eggs and larvae. Advantage II contains imidacloprid and pyriproxyfen, which is an IGR or insect growth regulator. The pyriproxyfen is the chemical which prevents the growth of new flea eggs and larvae.
The original Advantage (Advantage 18 or sometimes called Advantage I) does not contain these ingredients and will not work as well to stop fleas on your cats. Additionally, fleas are evolving to be more resistant to flea medications which requires new formulas to effectively fight the fleas.
You want to make sure to get the newest formulas, or the old stuff may not even have any effect on your flea problem.
Larger cats require more strength to kill all of the fleas. Be sure to pick the Advantage II that corresponds to your cat’s weight.
Where to buy Advantage & Which one to get
If you have larger cats 9 pounds or over, then Bayer Advantage II Purple 6-Month Flea Control for Cats 9+ lbs.
If you have a smaller cat under 9lbs, then you’ll want Bayer Advantage II Orange 4-Month Flea Control for Cats 5-9 lbs.
Hi. I have found the following information:
“Advantage II for large dogs is exactly the same product as Advantage II for cats.
Dosing Advantage II for large dogs properly will give you the same effect as if you had purchased Advantage II for cats. The size of the dose is the only difference with this product.
If you compare the ingredients on the labels, you will see that they are identical. NOTE: this is not so for Advantage Multi.
Actually, Advantage II (or any flea medication) for dogs is not exactly the same as for cats. While the ingredients may be the same, the active chemical in the medication is not present in equal parts throughout the whole dose. This means that you cannot simply use Advantage for dogs and lessen the amount, because although you may use less liquid, it is still very possible that the smaller amount actually contains more of the chemical than it should which results in an overdose. This can lead to disasterous results for your cat, including death.
Lots of internet sellers try to tell you its perfectly safe, but that is only because they want to sell you their dodgy product. Never use any flea medication for dogs on a cat. Don’t just take my word for it, ask your vet and watch them shake their head with frustration at the idea of using dog flea meds. Stick to Advantage II for cats and keep your kitties healthy and safe.
A local flea market seller has a bunch of backstock for Advantage 1… I bought some of it because it was really cheap, but it didn’t work on the fleas. I thought that Advantage was just no good but a friend linked me to this article on the changes with Advantage 2, so I tried it out and sure enough it killed the fleas! I have tried some of the other flea treatments also and so far the new Advantage 2 is working best.
I was confused about the differences with advantage 2, but this info was exactly what I needed. Just ordered some for my kitties, thanks for the cheapest link!!