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K9 Advantix II XL Dog Vet-Recommended Flea, Tick & Mosquito Treatment & Prevention | Dogs Over 55 lbs. | 3-Mo Supply

  • Based on 40,671 reviews
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Availability: In Stock.
Fulfilled by Amazon

Arrives Thursday, Dec 26
Order within 14 hours and 9 minutes
Available payment plans shown during checkout

Size: 3 Pack


Style: XL Dog only


Features

  • Contains one 2-pack of K9 Advantix II for Extra Large Dogs over 55lbs and one 1-pack of K9 Advantix II for Extra Large Dogs over 55lbs. Do not use on cats.
  • K9 Advantix II Extra Large Dog 30-day treatment & prevention protects dogs over 55 lbs. from fleas, ticks, mosquitoes, biting flies and lice
  • Kills fleas within 12 hours of application
  • Vet-recommended formula kills & repels on contact so fleas dont have to bite your dog to die
  • Easy-to-apply topical treatment is fragrance-free and waterproof after 24 hours
  • No prescription needed

Description

K9 Advantix II Extra Large Dog is the veterinarian-recommended formula that helps defend your dog against five pests: fleas, ticks, mosquitoes, biting flies and lice. And unlike other treatments, K9 Advantix II kills and repels fleas, ticks and mosquitoes. K9 Advantix II topical treatment gets straight to work killing fleas on dogs within 12 hours of initial application. This formula stops existing flea infestations and prevents new ones by killing adult fleas on contact so they can’t lay eggs and they don’t have to bite your dog to die. K9 Advantix II Extra Large Dog topical, spot-on formula makes application simple - going on in seconds. You’ll also love that K9 Advantix II is fragrance-free and waterproof after 24 hours of application. K9 Advantix II pest protection is effective on both indoor and outdoor dogs. K9 Advantix II Extra Large Dog is a trademark of Elanco or its affiliates.


Date First Available ‏ : ‎ October 6, 2022


Manufacturer ‏ : ‎ K9 Advantix


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Thursday, Dec 26

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews


  • Great product
Size: 4 Pack Style: XL Dog only
We’ve used this preventative on our puppies for two months now. We have 4 acres next to our house that are harvested for hay, so my dogs of course like running through the tall grass. I’ve only seen one tick on each of them, a very low amount compared to what I would expect, so I consider this a win. For reference, our dogs (Great Pyrenees) were 60-70 lbs the first month and 70-80 lbs the next month. I found that there was plenty of medication in each tube for each dog. It didn’t seem to irritate their skin either. I would definitely use this preventative again. ... show more
Reviewed in the United States on August 1, 2023 by Natasha W.

  • Takes a while but WORKS GREAT!
Size: 2 Count (Pack of 1) Style: XL Dog only
My dog had an allergic reaction to fleas and my next vet appointment wasn’t available until a week and a half so I tried this product to help ease my dog a little and in the vet I let them know she has fleas and etc, when they came back they said they didn’t find any fleas so whatever I used helped and they give her pills for the allergies but works great! It may take a while for it to notice. My dog stopped scratching hard after like two days. ... show more
Reviewed in the United States on August 3, 2023 by Edwin

  • Dogs are a lot better !
Size: 4 Pack Style: XL Dog only
My one dog was having a bad skin reaction from fleas and worms so after using this flea medicine and the other worm medicine, the dogs actually healing up and doing good . It also came faster than I expected .
Reviewed in the United States on August 15, 2023 by cody

  • Makes living in the woods way more comfortable
Size: 1 Pack Style: XL Dog only
I’m always nervous with putting things on my dog so I use them on me first to make sure he will be ok, I have been flea n tick free. The mosquitoes and flys have never bothered me and I would definitely use agin not just my dog but me also . We live in the woods and this has made life easier. I do enjoy watching my friends get bit n knowing I won’t. I wish they made these for lantern flys ... show more
Reviewed in the United States on July 24, 2023 by Jeana horst

  • This is the only non vet flea prevention that works
Size: 4 Pack Style: XL Dog only
I have lots of animals and I cannot afford hundreds of dollars a month in flea medicine at the vet. So I decided to give K9 Advantix a shot. And I’m so glad I did because the other product frontline. Was just not killing the fleas. They were infested but as soon as I put K9 Advantix on, they were dead within 1 day! Now it is a little expensive especially if you have 8 dogs like me. But it is a lot cheaper than at the vet and it works just as well. In my opinion. I also like that it repels in kills mosquitoes. Now it is not a heartworm prevention. My dogs are already on that, but it does prevent them as well. Overall, I think this is a great product. I just wish it was a tiny bit cheaper but if you want something that’s going to work this is it. If I can’t eat dinner one night so my dogs can be flea and tick free it’s worth it. ... show more
Reviewed in the United States on June 21, 2023 by Ashed

  • Flea Meds
Size: 4 Pack Style: XL Dog only
The only stuff that works on my dogs. I will never try anything else ever. I've had this for all my dogs and the fleas never became immune to this.
Reviewed in the United States on August 14, 2023 by Lisa Nicole

  • No ticks
Size: 2 Count (Pack of 1) Style: XL Dog only
My dog was having ticks, after putting this on her haven’t seen another. Great product
Reviewed in the United States on August 22, 2023 by Amazon Customer

  • Great value for money
Size: 1 Pack Style: XL Dog only
Our vet was happy that we use this product, and it’s much more affordable than many of the prescription options.
Reviewed in the United States on August 17, 2023 by R

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