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K9 Advantix

K9 Advantix II Medium Dog Vet-Recommended Flea, Tick & Mosquito Treatment & Prevention | Dogs 11-20 lbs. | 6-Mo Supply

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Condition: New
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Availability: In Stock.
Fulfilled by Amazon
Arrives Saturday, Jul 11
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Size: 6 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: 1.76 ounces


Active Ingredients: Imidacloprid, Permethrin, Pyriproxyfen


Item Volume: 6 Milliliters


Allergen Information: Allergen-Free


Dog Breed Size: Medium


Unit Count: 6 Count


Age Range (Description): 7 weeks and older


Is Discontinued By Manufacturer ‏ : ‎ No


Product Dimensions ‏ : ‎ 7.9 x 5 x 2.3 inches; 1.76 ounces


Item model number ‏ : ‎ 86315122


Date First Available ‏ : ‎ October 5, 2004


Manufacturer ‏ : ‎ Elanco US Inc


Best Sellers Rank: #435 in Pet Supplies (See Top 100 in Pet Supplies) #6 in Dog Flea Drops


#6 in Dog Flea Drops:


Customer Reviews: 4.4 4.4 out of 5 stars (33,673)


Brand Name: K9 Advantix


Age Range Description: 7 weeks and older


UPC: 724089203809


Global Trade Identification Number: 09


Manufacturer Part Number: 86315122


Model Number: 86315122


Unit Count: 6 Count


Included Components: 6 MONTH K9 Advantix II TEAL for Medium Dogs (11-20 lbs)


Warranty Description: Available from manufacturer upon request


Manufacturer: Elanco US Inc


Item Type Name: Topical


Item Form: Topical


Scent Name: Unscented


Dog Breed Size: Medium


Pet Type: Dog


Target Species: Dog


Item Weight: 1.76 ounces


Volume: 6 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: Saturday, Jul 11

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

    • After half a year of fleas, switching to this product completely got rid of them!
Size: 2 Pack
Cannot recommend enough! I live in the middle of the mountains next to a large national forest. There's deer, beer, turkey and all sorts of wildlife moving through my yard and in the woods year round, visibly agitated by fleas. My dog of 14 years finally got fleas (she's an inside dog with lots of outdoor playtime), as I've been thorough with checking her fur during brushings and baths. I usually just give her monthly flea baths which sufficed, but after a neighbor clear cut their property I've had an influx of wildlife on my property and I think that contributed to my dog getting fleas, I'm not sure. Regardless, she had fleas and they became an irritating presence within my home. Unfortunately, there's plenty of carpet for them to hide in and lay eggs. Yuck! I tried everything to get rid of them! Carpet powders, flea baths (different brands), furniture spray, cheap flea drops.. nothing worked. I battled with them for almost 6 months!! My poor dog was waking up constantly scratching and pacing back and forth throughout the house. I felt like an awful parent and was going crazy before finally deciding to look into the more expensive options.. Now, considering how much I spent on cheaper alternatives that didn't work or get rid of the problem at the source, I really wish I would've went straight for the higher priced option first. Within a matter of weeks of using this product I saw a quick decline in fleas inside the house and on my dog. Within one to two months, they were completely gone! I was in complete shock. I cannot praise this product enough. Maybe it's so effective on the fleas in my area since I live in the rural countryside where they're not used to it, as opposed to city fleas, so your mileage may vary. But for me this was a miracle product and I will be using this as a preventive measure in the summer months, with a periodic dose in the winter. If you struggled with fleas for months and months like I have, you will know the complete relief that comes with a flea-free home. Don't skimp! It may be more expensive than the alternatives but trust me with I say I tried all of them and nothing came close to getting rid of them, whereas this treatment was so fast and effective I was left nearly crying when I saw my sweet dog sleeping soundly through the night. :) ... show more
Reviewed in the United States on September 16, 2025 by Vincent
    • Thankfully, it works!
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
    • Does not kill fleas
Size: 6 Pack
I have used these for years and the last 3 months supply has been a disappointment they are not killing the fleas at all. My babies still have fleas crawling all over them after application. I will no loner be buying this product.
Reviewed in the United States on January 26, 2026 by M. Edwar
    • Watch for burns when the weight is close between doses.
Size: 2 Pack
After nexguard plus was found to be causing my frenchie liver and pancreatic issues for almost two years, I decided to try this instead. Caused skin burns on my 27lb frenchie... got the smaller breed dose after that and monitored his skin closely after and it was fine. Just beware and watch their skin after application when the weight is close between doses. I went by the weight for the dose and the smaller breed dose did not cause the burns and is still effective treatment. ... show more
Reviewed in the United States on April 29, 2026 by Ashlee C.
    • Best Product
Size: 4 Pack
Best product! I have a few dogs and I have tried many different things and this is the only thing that works. Thank you
Reviewed in the United States on May 23, 2026 by Barbara
    • This treatment works
Size: 1 Pack
I’ve tried other brands in the past with less than great results . I’m happy to say my little guy Johnny Rocco is now flea free and this was confirmed by his mobile groomer who bathes him cuts his hair and would see fleas if they were on him . On his recent groomer experience she told me nope no fleas not even dead flea eggs . Count me as a happy customer with this flea treatment . ... show more
Reviewed in the United States on May 6, 2026 by Johnny Rocco
    • Works so, so. Not very well.
Size: 2 Pack
Effectiveness, maybe 60%. Our dog is an indoor dog that we walk for potty breaks. The area surrounding our home is sprayed by a pest control service. I will not buy this product again.
Reviewed in the United States on January 16, 2026 by Ms. V
    • I use this and it works for all 6 of my dogs.
Size: 6 Pack
I have used this for years. You apply to their back. It is easy to use and not messy. My dogs have not gotten fleas or any other bites. I will continue to use. It works well and lasts for the month if not longer. The dogs do not notice it on them. Do not scratch or try to lick it. Great for the price. I have not noticed any side effects. ... show more
Reviewed in the United States on January 27, 2026 by Laura Rodriguez

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