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K9 Advantix

K9 Advantix II XL Dog Vet-Recommended Flea, Tick & Mosquito Treatment & Prevention | Dogs Over 55 lbs. | 6-Mo Supply

  • Based on 45,950 reviews
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Availability: In Stock.
Fulfilled by Amazon
Arrives Tuesday, Jun 24
Order within 22 hours and 6 minutes
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Size: 6 Pack


Style: XL Dog only


Features

  • 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. 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 Extra 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 over 55 lbs. to use K9 Advantix II Extra 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 Extra Large Dog is a trademark of Elanco or its affiliates.

Brand: K9 Advantix


Item Form: Topical


Scent: Unscented


Item Weight: 0.1 Pounds


Active Ingredients: Imidacloprid, Permethrin, Pyriproxyfen


Item Volume: 24 Milliliters


Allergen Information: Allergen-Free


Age Range (Description): 7 weeks and older


UPC:


Is Discontinued By Manufacturer ‏ : ‎ No


Product Dimensions ‏ : ‎ 7.75 x 1 x 4.25 inches; 1.6 ounces


Manufacturer recommended age ‏ : ‎ 1 month and up


Item model number ‏ : ‎ 81520429


Department ‏ : ‎ Flea & Tick


Date First Available ‏ : ‎ March 20, 2007


Manufacturer ‏ : ‎ Elanco US Inc


Country of Origin ‏ : ‎ Germany


Best Sellers Rank: #110 in Pet Supplies (See Top 100 in Pet Supplies) #3 in Dog Flea Drops


Item Weight: 1.6 ounces


Department: Flea & Tick


Manufacturer: Elanco US Inc


Country of Origin: Germany


Item model number: 81520429


Date First Available: March 20, 2007


Item Package Dimensions L x W x H: 6.65 x 4.37 x 1.42 inches


Item Dimensions LxWxH: 7.75 x 1 x 4.25 inches


Item Weight: 0.1 Pounds


Brand Name: K9 Advantix


Target Audience Keyword: dogs


Directions: Application Instructions 1. Use only on dogs. DO NOT USE ON CATS or other animals. 2. The dog should be standing for easy application. Evenly apply the entire contents of the K9 Advantix® II tube to four to six spots on the top of the back from the shoulder to the base of the tail. 3. At each spot, part the hair until the skin is visible. 4. Place the tip of the tube on the skin and gently squeeze to expel a portion of the solution on the skin. 5. Do not apply an excessive amount of solution at any one spot that could cause some of the solution to run off the side of the dog. 6. Do not get this product in your dog’s eyes, or allow your dog to ingest this product.


Model Name: K9 Advantix II


Color: Extra-Large Dog only


Size: 6 Pack


Age Range Description: 7 weeks and older


Number of Items: 6


Style: XL Dog only


Breed Recommendation: Extra Large


Specific Uses for Product: Parasites


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Tuesday, Jun 24

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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Similar Products

Top Amazon Reviews

    • The safest and most effective tick protection - ticks fall off just from touching the fur
Size: 6 Pack Style: XL Dog only
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. ... show more
Reviewed in the United States on June 4, 2025 by yishin
    • This will get rid of fleas on large dogs in one dose
Size: 6 Pack Style: XL Dog only
Review Image by Tambi Rosendahl Tambi Rosendahl
This is my German Shepherd and I have tried many different brands of flea medicine for my dog, and after being applied, he would itch and itch and itch as if I never gave him any medicine at all. This is the first brand that I put it on and he stops itching within 24 hours. I hate watching him scratch himself and cry because he’s itching from fleas. He’s a big dog. He has lots of fur. This medicine works within the 24 hours. The negative is it leaves a waxy greasy buildup behind his neck where I deposit it for about four days, but it does not smell. It just looks oily. I will take the oily look any day over him being uncomfortable and itching. In the past, I would end up using two treatments out of other brands and he would still itch so this one is for bigger dogs and it definitely covers him completely for 30 days. I do put a new one on every 30 days just because I don’t want fleas in the house. It’s not easy to find a good flea medicine that actually works this one. I promise you does so it’s worth the extra money because I only have to use one packet every 30 days not to like I do with other brands. ... show more
Reviewed in the United States on May 28, 2025 by Tambi Rosendahl Tambi Rosendahl
    • Flea death commeth!
Size: 2 Pack Style: XL Dog only
Dealing with a flea problem and this was recommended. It is definitely a walking flea killer. Our dog is 80lbs. After I apply this I see dead fleas on her bed and the ones still on her are moving at a fraction of the speed. We reapplied after 3 weeks due to her weight and this is for dogs 55lbs. Cannot let the fleas get a moment of rest. This is our first issue with fleas after a lifetime of having pets and it is a nightmare so I empathize with those going through it. I vacuum daily in the main bedroom. No pets on the bed for our sanity to have one space in the house that is for sure 100% flea free. Yard was sprayed and bought Nyguard to spray in the house. We do everything natural so it has been sad to turn to chemicals but when you become desperate you cave to what works best. I've tried essential oils and not sure how much that deters fleas. We also have a small dog and a cat. Pest guy says squirrels are main carriers for fleas so that is all we can figure out for how they got here. Or the cat that does wander at night. Also weekly baths on the dogs. The cat got a bath but he is black and I have yet to see a flea although he is always scratching. Also using homeopathy remedy so look that up. Good luck! ... show more
Reviewed in the United States on April 23, 2025 by Shalker
    • Effective flea treatment
Size: 6 Pack Style: XL Dog only
So far so good. This seems to be a very effective topical treatment. I have 5 dogs and some very annoying, wandering flea infested neighboring cats. I have tried multiple flea treatments for my dogs that were not the greatest. And last year we had the same issues with fleas. It has been almost a week and it not only killed current fleas but I haven’t seen anymore so far. Hopefully it lasts the whole month or at least 3 weeks and I will treat again. Thank you Advantix for giving my fur babies the relief they deserve and need. ... show more
Reviewed in the United States on June 8, 2025 by love to read
    • Worked on my Great Pyrenees
Size: 4 Pack Style: XL Dog only
The day after applying this product on my Great Pyrenees, I noticed a few blood filled ticks falling off of him. I didn't know he had such large ticks on him. GP have very thick double coats and getting down to the skin is difficult. I'm pleased with this product.
Reviewed in the United States on June 6, 2025 by William Dixon
    • Gone
Size: 4 Pack Style: XL Dog only
My dalmatian and shepherd were getting destroyed by fleas. I bathed and flea combed both but they kept coming back. We used K9 Advantix and the next day I noticed all the fleas were gone. It has been several days now and they are still gone. Very effective.
Reviewed in the United States on June 6, 2025 by Renee
    • Fleas gone in a flash
Size: 6 Pack Style: XL Dog only
Great product and it works. We have 5 dogs and none have fleas thanks to this product. Our Pomeranian got fleas so we had to treat all the dogs and we applied this and no fleas since. ( Note we got the small dog size of this product for the Pomeranian) Great prove if you have multiple dogs to treat and it's easy to apply. Directions are easy to follow. ... show more
Reviewed in the United States on May 25, 2025 by tricia

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