K9 Advantix II Large Dog Vet-Recommended Flea, Tick & Mosquito Treatment & Prevention | Dogs 21-55 lbs. | 2-Mo Supply (Packaging may vary)
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Availability:
In Stock.
Arrives
Monday, Jul 13
Size: 2 Pack
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 don’t 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 Name: K9 Advantix
Age Range Description: 7 weeks and older
UPC: 724089060716
Manufacturer Part Number: 86314940
Model Number: 86314940
Unit Count: 2 Count
Included Components: 2
Warranty Description: No_warranty
Manufacturer: Elanco US Inc
Item Type Name: Topical
Best Sellers Rank: #317 in Pet Supplies (See Top 100 in Pet Supplies) #7 in Dog Flea Drops
ASIN: B00N7DEBN4
Customer Reviews: 4.4 4.4 out of 5 stars (44,248) 4.4 out of 5 stars
Item Form: Topical
Scent Name: Unscented
Dog Breed Size: Large
Pet Type: Dog
Target Species: Dog
Item Weight: 0.02 Pounds
Volume: 5 Milliliters
Allergen Information: Allergen-Free
Active Ingredients: Imidacloprid, Permethrin, Pyriproxyfen
Frequently asked questions
If you place your order now, the estimated arrival date for this product is:
Monday, Jul 13
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.
To initiate a return, please visit our Returns Center.
View our full returns policy here.
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Similar Products
Top Amazon Reviews
Size: 6 Pack
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.
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Reviewed in the United States on April 29, 2012 by A. Waldron
Size: 6 Pack
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.
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Reviewed in the United States on March 14, 2015 by Elle
Size: 6 Pack
Works great on my 2 Corgis.
Reviewed in the United States on June 25, 2026 by Tyler Hinkelman
Size: 2 Pack
I read, researched & wanted to pull my hair out! I got my grand dog & needed something quick to combat fleas! This was #3 on the list I found & Amazon had it!! It arrived next day, easy application! It worked immediately and effectively! It came in a 2pk for a great value!
Reviewed in the United States on May 25, 2026 by Mary Baker
Size: 4 Pack
This was a good buy compared to purchasing at the veterinary business. I have used this product for many years. I always ask my vet which product is more effective for current year. Sometimes Frontline is better. Easy to apply, good quality. And definitely not a dupe..
Reviewed in the United States on June 27, 2026 by Prissy
Size: 2 Pack
Kills fleas and haven't noticed any ticks. I wonder, however, that the size range seems so vast. My 22 pound Yorkee qualifies as a large dog, same as his 50 pound "co-worker".
Reviewed in the United States on June 22, 2026 by RuthieWoof
Size: 2 Pack
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.
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Reviewed in the United States on June 10, 2025 by Amazonshopper
Size: 1 Pack
It seems to work, but I expected better results. Application was easy and there were no side effects, which I appreciated. However, I didn't notice a huge difference, so I'm still undecided if I would buy it again.
Reviewed in the United States on June 17, 2026 by Anna