

🐾 Stay ahead of pests—because your big dog deserves big protection!
K9 Advantix II XL is a vet-recommended, topical flea, tick, mosquito, biting fly, and lice treatment for dogs over 55 lbs. It kills fleas within 12 hours and repels pests on contact, preventing bites and disease transmission. Waterproof after 24 hours and fragrance-free, it offers easy monthly application without a prescription, ensuring your dog stays protected indoors and outdoors.













| Active Ingredients | Imidacloprid, Permethrin, Pyriproxyfen |
| Brand | K9 Advantix |
| Customer Reviews | 4.4 out of 5 stars 47,969 Reviews |
| Item Form | Topical |
| Item Volume | 8 Milliliters |
| Item Weight | 1.13 Ounces |
| Scent | Unscented |
A**E
Works great awesome I definitely suggested
UPDATE I don’t know what y’all all your people take your dogs to the vets instead of showing them online here that they can’t walk. The fur is falling out of the bleeding. That’s ridiculous. Take your dog to the friggin neck. Let the vet determine the cause exactly and then if it’s in clause because of this then Put a negative and state the fact that you took him to a vet and the vet did test and it was the closet because I’ve been using this product for 25 years on my dogs back then and my new dogs now my dogs I had 16 years ago dogs I had 10 years ago dogs I had 13 years ago my 16 1/2 year old cocker spaniel has had this from the day he could actually have this And I have never had a problem with that on any of my dogs especially him you know it got rid of the fleas and I noticed a few texts very easy to get off compared when I didn’t use it like if I skipped a couple of months and they had a dick and I was like oh my God and then I would try to get it off and it was a hassle. I mean, it did not pull up. Come out whatever And so I put them back on this every month originally and if they get a tick and I see it. I just need tweezers and it just pops right off no eggs inside nothing no problem with the weather did not cause any of my dogs ever itch or lose hair so I think you people have an undergoing problem with your dog that you did not address Prior to use this. Yes, I’m gonna blame you. Yes I’m blaming all you that people that has undermining problems with their dog and you don’t take them to the vet and you add this product on top of them. Yes, it probably will do something like that. SO I REPEAT, TAKE YOUR DOG TO THE GD VETERINARIAN PROFESSIONAL LET THE PROFESSIONAL DO THEIR WORK !!!! Oh, I also have one dog right now. I have three of them English mastiff and I have one of them that sits at my back gate in the dirt never has fleas never has sticks never has any. He lays in the dirt 185 pound and his head I can look it out right now his head is in it. His whole body lengthwise is in it and I swear he digs holes just you know it makes it cool.. and there’s a picture of him laying at the fence in the dirt. He loves it. I check them every day. Nobody has fleas. Nobody has anything so you people are doing something wrong. I’m gonna blame all of you. They have a problem and I’ll say it again again again they have underlining problem TAKE THEM TO THE VET VETERINARIAN HAVE THE VET, VETERINARIAN, TECHNICIAN, AND DOCTOR EXAMINE THE DOG TAKE SKIN GRAPHS WHATEVER THE BEST HAS TO DO. DON’T BLAME THE PRODUCT UNLESS YOU DID THAT AND IF YOU DID IT AND THEN DOCTOR RUNS TEXT AND SAID YES, IT WAS CAUSED BY THAT PRODUCT. WELL HENCE THERE YOU GO AND IT’S THE PRODUCT FAULT BUT A 99.999% IT’S NOT THE PRODUCT. Started having dogs when we first got married we have we had seven English mastiffs yeah it’s addicting and they had puppies and everything so anyways I’ve been using this on my dogs from year 2000 and I use them before that on my other dog so I’ve always used it really and I love it. I mean, I swear by it this stuff is great. My dogs do not get flea or I mean I have to put a spray on them to detail the mosquitoes, but don’t see my bugs biting them. It’s pricey, but it’s worth it. You don’t wanna have your dogs get Lyme disease or you know from ticks, I really suggest this. No bother my dog knock on wood you know in the other thing is I don’t use this year around. I only use it from spring until after fall. I don’t feel I really needed in the winter time. It’s too cold outside for anything to live so I’m up Northeast And I don’t seem to have any problem and they’re not using it as soon as spring hits that’s that boom they’re on it.
Y**N
The safest and most effective tick protection - ticks fall off just from touching the fur
I brought my dog to West Virginia, and thank God for Advantix II — because I’ve been finding half-dead ticks every single day (no joke) in places where she sleeps or rests. At first, I was confused. I thought "repels ticks" meant it would work like bug spray does for mosquitoes, keeping them away completely. But after looking into the active ingredient, permethrin, I realized that in this case, “repel” means: once a tick touches the treated fur, it becomes so irritated or neurologically impaired that it can’t bite, can’t hang on, and eventually just falls off and dies. That’s still so much better than PetArmor, Frontline, or any of the oral preventatives (like Simparica or NexGard), which require the tick to bite the dog before it dies. No thanks. Every tick I’ve found so far had already dropped off my dog before it had a chance to bite her and feed — exactly what you want in a tick-heavy area. I’ve also tried Wondercide (cedar oil). It works okay for fleas, but it’s just not effective for ticks, especially not in the long term. Its protection wears off after 2–4 hours. I learned the hard way — my dog caught Lyme disease, developed joint pain and a limp. Thankfully, doxycycline helped and she’s okay now, but it required a full 28-day antibiotic course. I would never use oral flea/tick medications. Just ask around — you’ll hear plenty of stories about dogs having seizures after taking them. For me, that risk isn’t worth it. If you have a cat at home, unfortunately Advantix II may not be right for your household — permethrin is toxic to cats (especially when wet). But if you don’t have cats, I highly recommend this product to all dog owners. Tick-borne diseases are no joke. Fleas are annoying — I’ve had to go through the nightmare of clearing an infestation — but at least they just suck blood without causing life-threatening illness. Ticks, on the other hand, can transmit Lyme, Ehrlichia, Rocky Mountain spotted fever, and more. So if you live somewhere warm, humid, grassy, or deer-heavy — do your dog a favor and get Advantix II. It’s been a lifesaver for us.
K**B
Fast shipping great product
Good product always works well with our dogs without any reactions easy ordering super fast shipping with Amazon. You can’t go wrong.
R**A
Always Comes Through! (Except for 1 of our dogs that is allergic!)
We've tried soooo many flea products over the years and honestly...most of them barely do anything for our dogs. K9 Advantix II is the one we always end up coming back to because it actually works! It works pretty quickly and it keeps them flea free for the whole month! It's also super easy to apply! That said...one of our dogs just can't handle it. We've seen bald spots and even more itching after using it, so definitely keep an eye on your pup when trying it for the first time. But for our other two dogs? Perfect results every time! We'll absolutely keep using it for them!
C**T
Only thing that works
K9 Advantix 2 is the only thing that works for the itchy bugs here in Oklahoma. This is a 2 pack for XL dogs. I bought it for my corgis, splitting one tube between them (they're 30lbs each). I find it to be a much more cost effective way of treating them. Easy to use, simply run the open tube up their spine from tail to collar. Just avoid giving them a bath for a few days. Product doesn't work "instantly". It takes a day or two to kick in.
J**R
Effective for flea and tick prevention
I've used this product for well over a decade on all my dogs, with excellent results. In addition to protecting against fleas, it is also quite effective against ticks. Living in an area where ticks are plentiful, that is very important to me. It's a cost effective way to protect my dogs and myself, and I don't worry that my dogs will be scratching and miserable, or that the effects will not be long-lasting. Highly recommended.
R**E
Works good!!!
Works well. Would recommend for fast treatment. Will be using again. Cheaper and just as effective as other name brand products.
B**H
Didn’t work for my dogs anymore
Used to work great. Didn’t last a month. Only got two weeks out of it. My vet says fleas get immune to stuff after a while
Trustpilot
2 weeks ago
3 weeks ago