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K9 Advantix

K9 Advantix II Medium Dog Vet-Recommended Flea, Tick & Mosquito Treatment & Prevention | Dogs 11-20 lbs. | 2-Mo Supply

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Condition: New
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Availability: In Stock.
Fulfilled by Amazon
Arrives Monday, Aug 18
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Style: Medium Dog Only


Size: 2 Pack


Features

  • K9 Advantix II Medium Dog 30-day treatment & prevention protects dogs 11-20 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 Medium 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 Medium 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 11-20 lbs. to use K9 Advantix II Medium 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 Medium Dog is a trademark of Elanco or its affiliates.

Brand: K9 Advantix


Item Form: Topical


Scent: Unscented


Item Weight: 0.32 Ounces


Active Ingredients: Imidacloprid, Permethrin, Pyriproxyfen


Item Volume: 2 Milliliters


Allergen Information: Allergen-Free


Dog Breed Size: Medium


Age Range (Description): 7 weeks and older


UPC:


Is Discontinued By Manufacturer ‏ : ‎ No


Product Dimensions ‏ : ‎ 1 x 4.38 x 4.75 inches; 0.32 ounces


Item model number ‏ : ‎ 86314991


Department ‏ : ‎ Flea & Tick


Date First Available ‏ : ‎ January 26, 2014


Manufacturer ‏ : ‎ Elanco US Inc


Best Sellers Rank: #448 in Pet Supplies (See Top 100 in Pet Supplies) #7 in Dog Flea Drops


#7 in Dog Flea Drops:


Customer Reviews: 4.4 4.4 out of 5 stars 32,411 ratings


Item Weight: 0.32 ounces


Department: Flea & Tick


Manufacturer: Elanco US Inc


Item model number: 86314991


Date First Available: January 26, 2014


Item Package Dimensions L x W x H: 4.72 x 4.37 x 0.94 inches


Item Dimensions LxWxH: 1 x 4.38 x 4.75 inches


Item Weight: 0.32 Ounces


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 two or three 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: Medium Dog only


Size: 2 Pack


Age Range Description: 7 weeks and older


Number of Items: 1


Style: Medium Dog Only


Breed Recommendation: Medium


Specific Uses for Product: Parasites


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Monday, Aug 18

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To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Similar Products

Top Amazon Reviews

    • Thankfully, it works!
Style: Medium Dog Only Size: 1 Pack
We have fought fleas on all fronts in our hot and muggy rural area. Frontline and the generic version- useless. Sprayed the land, treated our home, sprayed our dog with an additional temporary spray. This is the first time we've ever had such problems. Dog was constantly scratching, visible fleas and flea dirt. Flea comb simply full of mature fleas and flea dirt. Two vet visits in which we were told the next step was a yearly and expensive treatment. Thankfully, found this on Google as vet recommended. Bought a dose here. It arrived yesterday and we immediately applied as directed to 15 lb dog. He was fine upon application. No major problems afterwards but did began to claw himself aggressively and nip at his paws. Found those relatively minor results on the carton safety data and saw no reason to be overly concerned. I did give him the dose of antihistamine as prescribed by our vet. I think the fleas were 'abandoning ship'! He became drowsy within about 40 minutes settled down and slept soundly all night. No raw spots or other problems today but he looks like a newer, improved dog today. He is basically white. Today there were no visible fleas or flea dirt. Yes! So glad we found this product, all I will buy again! Great customer support because I called the # on the product box today just to check his reaction. They were great. ... show more
Reviewed in the United States on July 23, 2025 by a customer
    • A decade of satisfaction
Style: Medium Dog Only Size: 6 Pack
For ten years, K9 Advantix II Medium Dog has been my go-to flea and tick preventative. My dog has remained completely pest-free, even in a high-risk area, demonstrating its consistent effectiveness month after month. Crucially, he has experienced absolutely no side effects – no irritation, no changes in behavior, just a happy, healthy pup. The application is simple. I highly recommend K9 Advantix II for reliable, long-term protection and peace of mind. ... show more
Reviewed in the United States on July 7, 2025 by Coquette07
    • Works well
Style: Medium Dog Only Size: 1 Pack
This product is effective when the puppy/dog does get fleas. After applying, in a matter of days all fleas are completely gone. As it is a chemical and chemicals have potential risks to both the animal and humans, I only use it when fleas are present vs. a monthly preventative/maintenance on the advice of my vet. ... show more
Reviewed in the United States on July 25, 2025 by Cindy Reid
    • My dogs are agreeable to the application
Style: Medium Dog Only Size: 4 Pack
Flea control on your furry babies is no joking matter. The struggle is real! I've tried so many different kinds of flea control that one is as bad as the other. I went to my local PetSmart and went directly to the flea prevention professional, the store manager. I asked her which flea prevention medicine she would use on her pets, and she went straight to K9 Advantix. So, it's go time. I purchased the K9 Advantix and had my fingers double-crossed for extra luck on the flea fiasco. I've used it a few times, and it does work at the beginning of the cycle, but doesn't make it to the end of the 4 weeks as advertised. I will say that it is easy to apply and my dogs seem agreeable to the application, I just wish it would last a few more weeks longer because flea control is very costly, especially when you have 3 dogs. ... show more
Reviewed in the United States on June 21, 2025 by Karen Cuervo
    • Our go-to product
Style: Medium Dog Only Size: 2 Pack
Works every time. This is our go-to flea control now. It's much more affordable than what they sell at the vet, and does just as good a job.
Reviewed in the United States on July 19, 2025 by The Schmidts
    • Works!
Style: Medium Dog Only Size: 2 Pack
Works great for our 4 dogs - 2 chihuahua mixes and 2 lab mixes. Zero fleas and any ticks are dead on them.
Reviewed in the United States on July 19, 2025 by Our View
    • She said towatch closely and let her know if the symptoms did ...
Style: Medium Dog Only Size: 6 Pack
I felt it was my responsibility to inform pet owners of possible side effects associated with Bayer Advantix II. I purchased this to use on my always healthy and energetic 7 yr. old Lhasa Apso. Approximately 2 hours after application he started showing signs of lethargy and in general refusing to walk. When he did walk he only took one or two steps and then immediately sat down and started scratching or biting his tail and/or the application points. He had never displayed these symptoms before and has always been extremely active, running, barking and doing his guard dog thing. I took him to the vet the next morning. She couldn't find anything specific and said that although it would be unlikely, it could be a reaction to the Advantix since it had been applied only hours before symptoms appeared. She said to watch closely and let her know if the symptoms did not go away. In the meantime I called Bayer's pet health line. The person I spoke to immediately recognized the symptoms and said that it was because of an adverse reaction by my dog to the permethrin used in Advantix, used to repels mosquitoes. It leads to something called paraesthesia which was described as a tingling or pricking (pins and needles) caused chiefly by pressure on or damage to peripheral nerves. Since the Bayer representative knew immediately the symptoms, it sounded like this is a somewhat common problem. I was told that the condition is only temporary and should go away in 24-72 hrs. She said that the pins and needles effect was so irritation that the dogs typically will not walk to prevent this pain or irritation. I was told that the best treatment was to remove the Advantix by giving the dog a bath with Dawn dish detergent. I was told that I could also apply some Vitamin E oil to the application points to relieve irritation. It has now been approximately 36 hrs since the bath with Dawn to remove the Advantix and my dog is still not back to normal. He seems to feel alright and will eat and drink, but he refuses to walk more than a few steps at a time without scratching and then just sitting down. I have had to carry him around so as not to aggravate the situation. Normally he is very active and runs constantly. We have also had to cancel our daily walks of 2 to 3 miles a day. I am closely monitoring his condition and if it doesn't improve by the 72 hr deadline given by Bayer, I'm going to have to take him back to the vet for further treatment. I also gave him a second bath with Dawn just in case I missed some of the Advantix the first time. I realize that there are possible side effects with any product or medication, however since the Bayer representative immediately knew exactly what I was talking about when I described my dogs symptoms, I feel that this problem is possibly more widespread than reported. I know many people use and swear by K9 Advantix II but after what I have seen I definitely do not recommend it. There are also other flea medications that contain permethrin and I would also advise against them also. I have always used Frontline in the past and have had no problems with it. Frontline does not contain permethrin. ... show more
Reviewed in the United States on October 15, 2015 by rlbuzz
    • Not worth it.
Style: Medium Dog Only Size: 4 Pack
Considering how much I paid for this, I expected it to actually work. It's not great. They only had a few fleas, to begin with, but they were irritating them, and jumping on me, so I thought it best, to get some kind of treatment. They're still scratching (especially my older, smaller dog), and i had fleas jumping on me, this morning. I applied it, two days ago! Would not recommend, considering the price. It's not really worth it. ... show more
Reviewed in the United States on July 21, 2025 by Jen Malcom

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