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K9 Advantix

K9 Advantix II Large Dog Vet-Recommended Flea, Tick & Mosquito Treatment & Prevention | Dogs 21 - 55 lbs. | 12-Mo Supply

  • Based on 42,422 reviews
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$150.94 Why this price?
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Size: 12 Pack


Style: Large Dog only


Features

  • Contains one 6-pack, one 4-pack, and one 2-pack of K9 Advantix II for Large Dogs 21-55 lbs. Do not use on cats.
  • K9 Advantix II Large Dog 30-day treatment & prevention protects dogs 21-55 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 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 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 Large Dog is a trademark of Elanco or its affiliates.

Brand: K9 Advantix


Item Form: Topical


Scent: Unscented


Dog Breed Size: Large


Date First Available ‏ : ‎ November 2, 2022


Manufacturer ‏ : ‎ K9 Advantix


Best Sellers Rank: #178 in Pet Supplies (See Top 100 in Pet Supplies) #5 in Dog Flea Drops


#5 in Dog Flea Drops:


Customer Reviews: 4.4 4.4 out of 5 stars 42,422 ratings


Manufacturer: K9 Advantix


Date First Available: November 2, 2022


Brand Name: K9 Advantix


Target Audience Keyword: dogs


Color: Large Dog only


Size: 12 Pack


Style: Large Dog only


Breed Recommendation: Large Breeds


Frequently asked questions

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Top Amazon Reviews

    • Reliable Protection—No Fleas, No Ticks, No Worries
Size: 4 Pack Style: Large Dog only
K9 Advantix II has been our go-to for years when it comes to protecting our dogs—especially with all the outdoor time they get on the farm. It works fast and effectively against fleas, ticks, and mosquitoes, and we’ve had zero issues since using it consistently. The application is simple: just part the fur and apply it along the back. It dries quickly and doesn’t leave a greasy mess. What I really appreciate is that it repels pests before they even bite, which gives me peace of mind—especially in the warmer months when ticks are everywhere. Our dogs haven’t had any adverse reactions, and they’re outside constantly—running through tall grass, woods, and around livestock. It’s held up through baths and light rain too, which is a big plus. If you live rurally or have active outdoor dogs, this is one of the best defenses out there. Worth every penny for the protection it provides. ... show more
Reviewed in the United States on April 21, 2025 by Eric T.
    • A very effective product
Size: 6 Pack Style: Large Dog only
We have been using this product for our huskies for 10 years now and we are absolutely satisfied; not a single tick bite. I highly recommend it for effectiveness and safety
Reviewed in the United States on May 29, 2025 by Gelashvili Zurabi
    • Works
Size: 1 Pack Style: Large Dog only
Our dog had so many ticks already this year, used this and have not found a single tock
Reviewed in the United States on June 3, 2025 by Amazon Customer
    • Our dog had a severe allergic reaction.
Size: 4 Pack Style: Large Dog only
Our dog had a severe allergic reaction to this. About 2-3hrs. after we applied it he started scratching, breathing heavily and running around. I bathed him twice and administered Benadryl. He's doing much better now. We'll monitor him the next few days and find an alternative flea and tick treatment. I can't give this product a bad review because I understand it can effect dogs differently. Update 48hrs after application: Because we bathed our dog as soon as he showed signs of a reaction and administered Benadryl, we lessened the severity of his symptoms. He's not twitching or biting at his tail. His breathing is normal and he's sleeping soundly. ... show more
Reviewed in the United States on May 26, 2025 by Pap K
    • Love it!
Size: 2 Pack Style: Large Dog only
The only product I will use.
Reviewed in the United States on June 3, 2025 by Ann M.
    • so pricey
Size: 2 Pack Style: Large Dog only
good product, but so many years after r and d were done, how does it stay so pricey?
Reviewed in the United States on May 26, 2025 by Randy A Mollner
    • Causes itching
Size: 4 Pack Style: Large Dog only
This product caused my dog (Shiba Ina) to itch at where I put it on his skin for several days. This previously never happened when using Bravecto. Can't speak to whether it works or not as he hasn't had fleas or ticks before, I'm using this as a preventative measure.
Reviewed in the United States on June 6, 2025 by Vel
    • Works like a charm.
Size: 6 Pack Style: Large Dog only
Worked pretty quick. After 12 hours my corgi/blue heeler was able to calm down from the scratching. She still had some fleas as I checked. After 24 hours, she was so relaxed after days of non stop scratching. It’s been 3 days and haven’t found a single flea.
Reviewed in the United States on May 9, 2025 by Adrian Galvan

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