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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

  • Based on 32,706 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Amazon
Arrives Sunday, Oct 5
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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: #489 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 32,706 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: Sunday, Oct 5

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!
Style: Medium Dog Only 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 wouldn't 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!
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
    • Great value
Style: Medium Dog Only Size: 6 Pack
Have used this brand for years on our shih-Tzus. Very effective. It controls the fleas and other bugs. Has a slight smell. Our babies have never had side effects from this brand. Does leave an oily residue for a few days. It’s a great value since it does work. Doesn’t make our dogs scratch.
Reviewed in the United States on September 15, 2025 by Gwendolyn
    • Wish it lasted the whole month
Style: Medium Dog Only Size: 1 Pack
Four stars because it only works two weeks for us instead of a whole month.
Reviewed in the United States on March 10, 2025 by amberly
    • Advantix 2
Style: Medium Dog Only Size: 2 Pack
Best flea medicine ever!!
Reviewed in the United States on August 23, 2025 by Callie Hunt
    • Precious is happy being without fleas
Style: Medium Dog Only Size: 4 Pack
Review Image by Shelia Barron Shelia Barron
This was a great buy and worth every penny, it says each one of the four vials of the drops last a month but they actually last longer than that and I mean 100% of fleas off the dog out of the house will not come near Precious!
Reviewed in the United States on September 24, 2025 by Shelia Barron Shelia Barron

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