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

  • Based on 39,778 reviews
Condition: New
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Availability: In Stock.
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Arrives within 30 days
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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


Target Species: Dog


Dog Breed Size: Large


Date First Available ‏ : ‎ November 2, 2022


Manufacturer ‏ : ‎ K9 Advantix


Best Sellers Rank: #163 in Pet Supplies (See Top 100 in Pet Supplies) #4 in Dog Flea Drops


#4 in Dog Flea Drops:


Customer Reviews: 4.5 4.5 out of 5 stars 39,778 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

If you place your order now, the estimated arrival date for this product is: within 30 days

This item is non-returnable:

Non-returnable due to hazmat safety reasons

View our full returns policy here.

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Top Amazon Reviews


  • Great Product! Will buy again!
Size: 2 Pack Style: Large Dog only
As a dog owner, K9 Advantix II Large Dog Flea, Tick & Mosquito Treatment is an absolute game-changer! Vet-recommended and highly effective, it provides unparalleled protection against fleas, ticks, and mosquitoes. With just one application, I can rest assured that my furry friend is shielded from these pesky pests, allowing them to enjoy outdoor adventures without worry. Plus, it's waterproof, so even swimming won't compromise its efficacy. Say goodbye to flea and tick worries and hello to peace of mind with K9 Advantix II! ... show more
Reviewed in the United States on April 15, 2024 by AHNA BAXTER

  • Works great
Size: 1 Pack Style: Large Dog only
I was looking for a product I could order without going through an expensive vet every time, that was also effective for my dog. This product comes as pictured with clear instructions and works great! No fleas for over a month! I started reordering as recommended. I highly recommend this product.
Reviewed in the United States on April 7, 2024 by KM

  • Advantix 2 works great. It truly repels as advertised especially the mosquitos ...
Size: 6 Pack Style: Large Dog only
Advantix 2 works great. It truly repels as advertised especially the mosquitos which is good since those are the thing to worry about heartworm. Frontline is getting tolerant, I always have far better results from Advantix 2. For anyone looking for full 4 weeks of perfect coverage, it just doesn't exist. Any topical solution will weaken as you near the 4th week but I have found Advantix 2 to be GREAT. This is a great Seller and cannot beat the price. This is my second time purchasing from this seller on Amazon for price but also quality of product not sold nearing expiration. Expiration doesn't MEAN BAD it means Weaker. OK... SO! What about Irritated Skin!? Don't BUY IT if your worried about that! Some dogs are extra sensitive or ALLERGIC. DONT buy a topical solution if that is a huge concern. IT DOESN'T MAKE THIS A 1 STAR product because your dog is allergic or sensitive. For god sakes, you are putting poison on them and that includes in any brand unless your getting a prescription for a Pill. Then there are other possible side effects. Accept That. Anything you choose has Pro and Con's. My dog has sensitive Skin. She will get a little pink when I use ANY topical solution. However Advantix 2 is well known for being kinda strong. So how do I manage it for my Furbaby??? Easy. Take the time to put the solution on in several places. NOT JUST ONE BLOB, because you're too lazy. I skip the base of the tail. I never understood this. My dog can lick there all she wants. But I go from base of head at the back of the skull and ever couple inches I squirt a little down till I get between the shoulder blades and even so much as a little bit below that on her back. This helps spread it out and not irritate her and make her itchy. Then again, my pup has allergies and she's on Zyrtec daily. But when I use to not spread it out she would seem uncomfortable, now she is fine with it. She is just sticky for a day. A Con is Advantix 2 is a little greasier and you get More of it. But frontline barely gives any and never seems to work past 2 weeks. So take your pick! After a day, I brush her out and there is no more sticky. I wait a week instead of 48 hours to bath her. I don't notice any lack of flea control after a bathing. I really think this product works for anyone in areas where Frontline is losing its effectiveness. Also, heartworm is a billion dollar scare tactic. The idea of it is terrifying however, it is also expensive and for anyone struggling to spend that kind of money per month on their pup. Or those who are concerned with the drug's effect on the body long term, or those that are allergic. Advantix 2 has that added benefit of the mosquito repellent if you're religious in your re-applications. So... yeah. You're going to see pictures of Poor Pink or Red skin. Statistically, there will ALWAYS be a % of animals that have an allergic reaction to inactive ingredients. However, as an owner of a dog with skin problems. Just be smart about spreading out the application and don't go putting detergents on your dog "washing it clean" because their skin got a little pink or irritated. THAT is what worsens the situation. And I have gone through skin and fur issues with my pup to know this. My dog is allergic to the grass. I know skin irritation. Or should I say She Knows. ... show more
Reviewed in the United States on March 14, 2015 by Elle

  • Works well to keep pests away from my pet
Size: 1 Pack Style: Large Dog only
We use this monthly on our mid size dog and it works well
Reviewed in the United States on April 2, 2024 by Mary

  • It worked when Frontline did not!
Size: 1 Pack Style: Large Dog only
I’ve used frontline for years and this time it did not work! Before I could get frontline on my white boxer she got a horrible case of fleas. So before I put on the frontline I gave her a bath with dawn dish soap “works great for killing flea “ so we got rid of what was on her wait for her to dry and then put frontline on her by that night she was cover in flea again. I gave it a couple of weeks too work it did not so I thought maybe be I did it wrong so repeat the process of bathing and waiting for her to dry and repeat the frontline same thing happened. So I read view and it seem some people are having trouble with frontline not working. Somebody recommended K9 Advantix so I did the same thing that did with the frontline, gave her bath wait for her to dry and than applied the K9 Advantix and it worked great haven’t seen a flea on her in over a week! It also protect against mosquitoes too frontline does not! Price is comparable to frontline. ... show more
Reviewed in the United States on August 15, 2023 by Kim Holtgrave Kim Holtgrave

  • Stop the Bite!
Size: 4 Pack Style: Large Dog only
Our SAR K9, Zydeco, takes oral medication for fleas and ticks, as well as heartworm. However, these systemic oral medications do NOT deter the insect from biting the dog, thus enabling the spread of disease. So I use this medication to PREVENT ticks from biting and latching on, in hopes of preventing Lyme Disease and other illnesses. Zydeco is a 45lb Australian Cattle Dog mix that is training for FEMA SAR/HRD K9 certification. We take him camping in tick-infested Missouri, as well as running him through tick-infested woodland, grassland and thick brush. After applying a month ago, we did find a tick after camping at Eisenhower State Park in Missouri. The tick had had several unknown hours to find a juicy spot to sink its pinchers and mouth into for a bloody feast. But no, the tick was still migrating through the fur and easy to remove. Just two months before starting the topical treatment I had found a tick only a few hours after SAR training. This one had dug in deep. After removing and killing the tick, he left behind a large welt and hard knot below the epidermis. After about six weeks the subcutaneous knot slowly resolved and thankfully Zydeco did not display any ill effects. UPDATED 06/30/2023 After using this product for 3 months we have had no ticks ATTACH to our K9. We have found 2-3 around on his skin, but they were either dead, nearly dead or had not bitten him. Our new vet does not sell this product (as it is over-the-counter, I presume). He suggested FRONTLINE Gold for Dogs. No where on the package or their website did it mention REPELLING Ticks, Flies or Mosquitoes. I called the 1-888 # to verify directly from FRONTLINE; indeed it was confirmed that FRONTLINE does NOT repel ticks. It is only effective after they bite, and by that time it’s too late as disease could be transmitted. Needless to say, I will be returning the FRONTLINE Gold and purchasing more ADVANTIX II ... show more
Reviewed in the United States on May 5, 2023 by Darren M.

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