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K9 Advantix

K9 Advantix II Large Dog Vet-Recommended Flea, Tick & Mosquito Treatment & Prevention | Dogs 21 - 55 lbs. | 4-Mo Supply

  • Based on 42,757 reviews
Condition: New
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Availability: 20 left in stock
Fulfilled by Amazon
Arrives Oct 25 – Nov 20
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Size: 4 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


Active Ingredients: Imidacloprid, Permethrin, Pyriproxyfen


Item Volume: 10 Milliliters


Allergen Information: Allergen-Free


Dog Breed Size: Large


Age Range (Description): 7 weeks and older


UPC:


Global Trade Identification Number: 91


Is Discontinued By Manufacturer ‏ : ‎ No


Product Dimensions ‏ : ‎ 7.75 x 1 x 4.25 inches; 0.63 ounces


Item model number ‏ : ‎ 86315041


Department ‏ : ‎ Unisex-Adult


Date First Available ‏ : ‎ March 4, 2011


Manufacturer ‏ : ‎ Elanco US Inc


Best Sellers Rank: #207 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 42,757 ratings


Item Weight: 0.634 ounces


Department: Unisex-Adult


Manufacturer: Elanco US Inc


Item model number: 86315041


Date First Available: March 4, 2011


Item Package Dimensions L x W x H: 4.72 x 4.37 x 1.46 inches


Item Dimensions LxWxH: 7.75 x 1 x 4.25 inches


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.


Country of Origin: Germany


Model Name: K9 Advantix II


Color: Large Dog only


Size: 4 Pack


Material: Plastic


Age Range Description: 7 weeks and older


Number of Items: 4


Style: Large Dog only


Breed Recommendation: Large


Specific Uses for Product: Parasites


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Oct 25 – Nov 20

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

    • Worked well for Fluke
Size: 6 Pack Style: Large Dog only
I recently moved from the cooler, mountainous region of SC to the warmer climate of middle GA to attend graduate school. I had been using Comfortis for two and half years on my dog, Fluke, without any problems. However, about two weeks ago, I felt a lump on her neck, and upon inspection, I discovered a tick. I began looking all over her body for more of these little pests, and found four more of them. Fortunately, Fluke is a rescue from a vet, and I don't have to bear the burden of expensive vet bills when something like this situation occurs. I was told that the Comfortis does not necessarily guard against ticks, and while it may have been effective in SC, the tick population in the heavily wooded river area in which I live now might be too much for the tablet to protect against for Fluke. I bought this product because it proffered to prevent ticks from attaching to the dog, and thus far, it has proven quite effective. Fluke, as her name suggests, is an unusual 25 pound lab/pit mixture. I purchased the product in the larger size because she is in between the medium and large dosing sizes, and I wanted to be sure that she had adequate protection. Fluke has been her usual happy self since I applied it to her. The directions indicated that you should apply in four to six spots on the dog, and I chose to apply to six, as to not have too high of a concentration in any area. I know that some people have reported having adverse reactions upon applying this product on their dogs, but I have noticed a trend in the reviews: most of the reviews are concerning smaller dogs. It might be that the formula is just too much for a smaller dog, but I'm not anywhere near an expert on the topic, just something that I have noticed. I am of the opinion that what it boils down to is this: all dogs are different, and what works well for one dog does not necessarily work well for others; the same could be said of medications for people, too. I'm just happy to have chosen a product that works well for Fluke. On another note, if you only need flea prevention, Comfortis is amazing, and much less messy than the topical products. While searching for more ticks, I never did find a flea on her! I hope that my review could be of some help, even though it is not very specific. UPDATE AS OF JULY 2013: I have brought home a 4 pound Pomeranian since my original post. I stand by what I stated in my previous post: this product works well for fleas, ticks, and mites in the warmer climate of middle Georgia in which I live. Barnaby, my little Pomeranian, has not had an adverse reaction to this medication, and Fluke, my lab/pit mixture, remains free of fleas and ticks, all the while not exhibiting any negative symptoms. For my little Pomeranian, I applied the medication to 4 separate places along his back, again to not have too high of a concentration in any one area. I purchased the smallest dose currently on the market, and although it was a little high for his small stature, it did not seem to phase him in any sort of negative ways. I wait, at a minimum, 72 hours before bathing my dogs, and I also do not bathe them for at least 5 days prior to application of the medication, as the oils within a dog's skin distribute the topical treatment. My dogs tolerate this medication well, and I have not found a flea or tick on either of them since I began using this product; however, I still will caution potential purchasers of this product: this product may not work well for your dog, just as some medications may not work well for you. Please, before you condemn the product as unsatisfactory, try to determine, and this may require the aid of a veterinarian, what your particular dog requires based upon breed, climate, and tolerance to topical flea prevention. I can only relate that this product works well for my larger dog and also my smaller dog within the area in which we currently live. Again, I hope that my update as to the effects of this product upon my smaller dog is helpful in your search for the right fit for your dog. ... show more
Reviewed in the United States on April 29, 2012 by A. Waldron
    • It works
Size: 2 Pack Style: Large Dog only
My dog was on a prescription medication before this. I had to stop her previous medication because it was out of stock for a while and when it was restocked, the price skyrocketed to $250 for a 6 month supply instead of the usual $120 that it was prior. There was a new generic version of her prescription but after reading the reviews on that, I didn’t want to risk my dog’s health. During that time of her not being on any preventative, we ended up with a flea problem in my area which we never had before. Since the fires, a lot of wildlife has been dropping by in my neighborhood and with wildlife comes fleas just hitching a ride with them. We fell victim to an infestation in our backyard and surrounding areas. I panicked and tried the holistic approach for months with DE, changing my dog’s diet, essential oils, etc to no avail. I had to try something because my dog is old and I really didn’t want to stress her by taking her to the vet for yet another prescription (which all had extremely negative adverse effects after doing plenty of research). I decided to try an OTC flea treatment and it was between this one and frontline. After doing more research, I opted for Advantix II since it was more effective than frontline (for my area). So glad I did because fleas were gone within a day. My dog has been on this for a year now and so far it is working. I did find a flea on her the other day right after we got back inside from our little walk and was able to grab it. I put it in a ziplock bag with a piece of my dogs shedded fur just to see if the treatment was still working since it had been 26 days since I used Advantix and within 2 hours of that flea crawling on her fur in that bag, it was dead. So I know for sure that this medication is working and working effectively at that. She was groomed two days prior to me finding a flea on her as well (she had a waterless bath and is wiped down with her dog wipes daily) - the bath and wipes didn’t minimize the effectiveness of this flea medication which is a huge plus! What I’ve learned throughout this whole process is that no treatment is going to immediately kill or prevent fleas or ticks - not even prescription medication - Advantix has saved me hundreds if not thousands of dollars on prescriptions and it’s still as effective as a prescription. It’s a win - win in my book and I will continue to use this year round to keep my dog protected. ... show more
Reviewed in the United States on June 10, 2025 by Amazonshopper
    • Great product that does its job.
Size: 1 Pack Style: Large Dog only
Vet recommended this product as an affordable flea prevention for our dog. It was very easy to follow instructions and apply. Took care of the current flea problem in the first month. Seemed to be safe for our pets with no adverse reactions. Didn’t seem to cause any excessive scratching like other products we have used in the past. Small tubes are easy to store if you buy ahead. Worked as intended. ... show more
Reviewed in the United States on July 5, 2025 by Rebekah B.
    • Easy to apply, flea free pets
Size: 4 Pack Style: Large Dog only
Has worked great on my dog for years. I would often forget the dates for the doses (it comes with sticker reminders that you can use to remind you of the next dose. Nothing to remind you to use the stickers 😁) I say this to say that the dose is durable, it would go longer than the month and my dog would still be flea free. It's very easy to use. You DON'T shower your dog before applying the dosage as it relies on your dog's natural oils to deliver the dose. It's applied at the base of the neck. So easy my 11 year old would do it as you just squeeze at the base of the neck. We would split the hair with the edge of the tube and make sure the liquid hit his skin and didn't stay at the hair. Very easy. We have yet to notice any side effects to our doberman. He can't get to it as it's at his neck. The liquid isn't runny and stays put, and doesn't leak or run off to other areas of his body. You don't shower them until maybe 3 days later to make sure it's effective. It kills fleas quick too. I can't say I've paid attention to how quick but he'll stop scratching by the next day. I will say that after years of use, fleas may be come resistant and the dose won't seem to work as well anymore, usually I just switch brands and come right back when I need too. ( I've experienced the same thing with Frontline) ... show more
Reviewed in the United States on July 7, 2025 by Leon Fam

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