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K9 Advantix II Large Dog Vet-Recommended Flea, Tick & Mosquito Treatment & Prevention | Dogs 21-55 lbs. | 1-Mo Supply

  • Based on 37,810 reviews
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Availability: In Stock.
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Arrives Sunday, Nov 24
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Size: 1 Pack


Style: Large Dog only


Features

  • 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. Fleas, ticks, mosquitoes and other pests not only cause discomfort; they may also transmit disease. Monthly use of K9 Advantix II is important to protect your dog against fleas that may cause transmission of tapeworms. This formula also kills fleas which may cause Flea Allergy Dermatitis and flea bite anemia. That’s why K9 Advantix II Large Dog topical, spot-on formula makes application simple - going on in seconds. It's easier than a flea collar and there are no hard-to-swallow pills. You’ll also love that K9 Advantix II is fragrance-free and waterproof after 24 hours of application. Check the product label for information on application and potential side effects. K9 Advantix II pest protection is effective on both indoor and outdoor dogs. Your dog should be at least 7 weeks old and weigh 21-55 lbs. to use K9 Advantix II Large Dog.For the ultimate convenience in care, K9 Advantix II is available over the counter – no prescription needed. And, you can stock up with 2-dose, 4-dose and 6-dose packs so you never miss a monthly treatment. Once K9 Advantix II is applied, your dog is ready to get right back to big-pup cuddles and racing around the park.K9 Advantix II Large Dog is a trademark of Elanco or its affiliates.


Brand: K9 advantix


Item Form: Topical


Scent: Unscented


Age Range (Description): 7 weeks and older


Item Weight: 0.01 Ounces


Active Ingredients: Imidacloprid, Permethrin, Pyriproxyfen


Item Volume: 1 Fluid Ounces


Target Species: Dog


Allergen Information: Allergen-Free


Product Dimensions ‏ : ‎ 4.25 x 0.88 x 4.75 inches; 0.01 Ounces


Item model number ‏ : ‎ 86145898


Date First Available ‏ : ‎ March 13, 2019


Manufacturer ‏ : ‎ Elanco US Inc


Country of Origin ‏ : ‎ Germany


Frequently asked questions

K9 Advantix II Large Dog Treatment is optimal for dogs weighing between 21-55 lbs. It is specifically designed to fit this weight range for effective flea, tick and mosquito prevention and treatment.

Each box of K9 Advantix II Large Dog Treatment provides a one-month supply. For ongoing protection, it is recommended to use the treatment once every month.

No, K9 Advantix II Large Dog Treatment is effective against fleas, ticks, and mosquitoes. It acts as a preventative measure to keep your pet from being infested with these pests, and can also treat existing infestations.

Yes, K9 Advantix II treatment is vet-recommended. It's a trusted choice among professionals for its effectiveness in preventing and treating flea, tick, and mosquito infestations in dogs.

Top Amazon Reviews

🚀 Abunda's Overview

This is our summary and key points to consider based on customer reviews.


Based on the reviews, K9 Advantix appears to be an effective product for flea and tick prevention in dogs of all sizes. The majority of users reported a noticeable decrease in flea infestation soon after product application, and additional features such as its ability to repel mosquitoes make it even more appealing. The testimonials also suggest that it outperforms similar products in the market, such as Frontline.

Pros

  • 🐾 Works effectively against fleas, ticks and mosquitoes
  • 😊 Easy to apply and non-irritating to the pet's skin
  • 🏞️ Suitable for outdoor pets and dogs in tick-infested areas
  • ✅ Has worked where other brands have failed

Cons

  • 💊 Some pets might already be too infested for the treatment to work right away
  • ⚠️ Medicine must reach the skin to be effective
  • 🧪 It can potentially inflame "hot spots" on dogs

Should I Buy It?

Definitely. K9 Advantix appears to be a highly effective product for not only treating but also preventing flea and tick infestations in dogs. While it is necessary to apply the product correctly and pay attention to potential inflammation of "hot spots", these concerns are minor when compared to the product's demonstrated efficiency.


  • 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

  • SIZE MATTERS!!!
Size: 2 Pack Style: Large Dog only
I purchased the “Large Dog” size for a 30 pound dog. This should have, IMHO, provided more than adequate coverage for the flea problem he has - but it’s been ~2 weeks and he is still barking at his butt. After some research, I learned that you MUST MAKE SURE that the medicine reaches the SKIN, not just the bottom of the fur next to the skin. And - if your treating a dog with “hot spots” - you may want to hold off and see your vet first because this medicine CAN - not always, but has the potential to further inflame these “hot spots” that itch so badly. Finally, always make sure you apply these drops every month on the same day of the month. And please don’t wait until the poor pooch is so irritated by the fleas that they become difficult to treat. Like my grandmother always said, “an ounce of prevention is worth a pound of cure” and with the heat bearing down on the USA this year, the fleas are out taking a bite out of every unprotected animal out there! Make sure you purchase the correct size for your dog, and if you have an animal that is closer to the heavier side, I’d recommend ordering the next size up, but always ask your vet when in doubt. It’s a good product all in all, but fleas are a problem best resolved sooner, not later. Good luck! ... show more
Reviewed in the United States on August 8, 2023 by SoCalgirl214

  • It works like it always has.
Size: 4 Pack Style: Large Dog only
I switched to K9Advantix from Advantage years ago because I moved to an area with A LOT more ticks. It has always worked for me and my dogs. I let my dog's Advtantix lapse for a few months, and then some cats brought a ton of fleas into our backyard, so I ordered this product as soon as I saw a flea jump off my dog as we were on my bed. That was 2 days ago. The product arrived yesterday, and the flea combs arrived today. I just combed my girl and found a single nearly-dead flea, so it's working. When I've gone hiking with my girl, I've always made sure her Advantix was up to date, and although I have found a few ticks on her - they were already falling off and dying (so, again, Advantix works). ... show more
Reviewed in the United States on July 27, 2023 by K. Williams

  • Works great!
Size: 2 Pack Style: Large Dog only
Fleas are horrible this year where I live in Southern California. I found several on my dog. After giving her a bath, letting her dry completely and then applying the Advantix, all the fleas disappeared. It’s been a little over two weeks since I applied the Advantix, and I still haven’t found any fleas on her. ... show more
Reviewed in the United States on August 12, 2023 by Christine Q

  • No more scratching!
Size: 2 Pack Style: Large Dog only
The order came in just a few hours so that was good! My poor dogs had some fleas that they got at the dog park and it broke my heart to see them jerk around quickly and bite at themselves. I haven't seen them do it once since I put this treatment on them. One is a husky and one is a lab and they are now sleeping peacefully without the little annoying pinch of fleas biting them! Easy to apply, no scent at all and didn't irritate their skin at all. ... show more
Reviewed in the United States on July 22, 2023 by Kerry L.

  • 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.

  • Worked effectively within 24 hours of application
Size: 1 Pack Style: Large Dog only
Great product and works instantly. My dog was invested with Fleas and shampoo bath did not help. Applying this liquid medicine on his back worked like a wonder.
Reviewed in the United States on August 18, 2023 by Hariharan Sunderraj

  • The best
Size: 4 Pack Style: Large Dog only
I tried to be cheap and bought a collar. This is the first year any of my dogs got fleas. Changed to this and have not seen a flea since.
Reviewed in the United States on August 14, 2023 by Demondog

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