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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 34,034 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Amazon
Arrives Thursday, Sep 3
Order within 11 hours and 53 minutes
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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: 9.07 g


Active Ingredients: Imidacloprid, Permethrin, Pyriproxyfen


Item Volume: 2 ml


Allergen Information: Allergen-Free


Dog Breed Size: Medium


Unit Count: 2 Count


Color: Medium Dog only


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: #540 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 (34,034)


Brand Name: K9 Advantix


Unit Count: 2 Count


Age Range Description: 7 weeks and older


UPC: 724089060631


Global Trade Identification Number: 31


Included Components: 2


Item Type Name: Topical


Manufacturer: Elanco US Inc


Model Number: 86314991


Manufacturer Part Number: 86314991


Warranty Description: No_warranty


Item Form: Topical


Scent Name: Unscented


Dog Breed Size: Medium


Pet Type: Dog


Target Species: Dog


Item Weight: 9.07 g


Volume: 2 ml


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: Thursday, Sep 3

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
    • As advertised
Size: 1 Pack
Works great, no problems with critters or skin reactions.
Reviewed in the United States on August 5, 2026 by Jhaub
    • Been using it for over 10 years
Size: 6 Pack
I live on the Gulf Coast. Mosquitos are a big part of life here and that is one of the main reasons I chose Advantix and stick with it. It repels and kills mosquitos. I have a miniature schnauzer, so her belly is pretty low to the ground and they love to lunch on her. This does the trick. As far as fleas: Never have had a one and fleas are terrible here. Never. Not. Once. I usually buy an entire year at a time so I'm never without because if you stop treatment, those fleas will find you. Biting flies, repels those too. Now we're on to ticks. I'll be honest, this does nothing for my dog and ticks. I do have a fenced in very small yard in the middle of downtown. There are no ticks here, so it's not a worry for me. When I first took her hiking is when I realized Advantix must be candy for ticks. She was covered. It didn't repel and it didn't kill them. I talked to the vet about it she said that others had said that about Advantix and she recommended I switch. I didn't want to because of the mosquitos so she told me about Virbac Preventic tick collar when we go hiking. I came home, went straight here and bought a 2 pack. It's not cheap but I tell you it works. Went camping and a few ticks were brave enough to jump on her but they struggled; they couldn't get a hold of her and they started getting weird and just fell off. None attached and only 3 tried it. So if you have a tick issues give that a try but as for Advantix and fleas/mosquitos/flies, just do it. Your furbaby will thank you. ... show more
Reviewed in the United States on February 13, 2014 by 2Drinkwaters
    • 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.
    • Love it
Size: 2 Pack
Love this product. Effective and so easy.
Reviewed in the United States on July 29, 2026 by Sharon Alexander
    • Must buy!!!!
Size: 2 Pack
I’ve tried so many things and nothing was working. I don’t usually have fleas but this year my dogs both got fleas and then brought it into the cats so I’ve tried three or four different products and nothing was working, so I finally got this and it worked perfectly we are finally free of fleas!!!
Reviewed in the United States on June 26, 2026 by Monica
    • EDIT! MONTH 3!
Size: 4 Pack
I bought this for my furbaby because I read the labels and did research and everything I found said it really worked but was very strong. Then, I read the 1 star reviews. I panicked and tried to cancel the order but it was too late because I got it same day. So I just researched more about the offending chemical and when I got the order and attempted to use the topical on my dog, but I couldnt get anything out. Call me silly, but I didn't know you had to cut the applicator to open it. Also it was such a small amount, very unexpected. From what I understand, my conclusion is that most of the accounts of sick dogs comes from the dog being able to lick the formula. The neurology problems, chemical burns and tremors, most of this, I assumed, was because the dog ingested it. Chemical burns from putting too much in one spot. Also, I have a pug and her fleas already drive her crazy so the restlessness wasn't new for me. However she did become a lot more vocal. I have these wipes for her that are soothing, and it instantly relieves itchiness. I looked at the places she was itching and use the wipes to sooth the skin. Last night she did scare me a little bit, because I know my dogs eyes and behavior and her eyes were absolutely what you would call "whale eyes" and it looks crazy, and she has the grimace that looks like a smile but its not, like her mouth barely open and she panted for awhile. I just gave her some love and helped her calm down enough to go to sleep. Anyway, we are now on day 2. I havent seen too many fleas come off her yet, but her itchiness has improved, which is shocking to me because I dont see any of the fleas on her bed or floor. The scariest effect so far, has been her whale eyes, and I think its because she's so incredibly itchy and restless. I will update this as we progress. But so far, so good, knock on wood! Edit; month 3 just passed of using this and it really is working very well. By the time it’s time for the next one, you can sometimes tell because you’ll see some fleas on her when she comes back from outside. Other than that, no complaints here! The first day she has it applied, she can get a bit moody with an attitude. But nothing ever severely wrong with her after taking it, other than a little bit itchy. ** TRY TO PUT THE SOLUTION ON THE SPINE OF THE BACK WITH THE DOG STILL. THIS WILL MAKE IT IMPOSSIBLE FOR THEM TO LICK IT OFF AND MAKE THEMSELVES SICK! My very sensitive pug has been quite satisfied with this product. ... show more
Reviewed in the United States on January 11, 2023 by Shauna Cartwright
    • Advantage flea control
Size: 1 Pack
My animals were covered with fleas and after I applied this they have quit scratching
Reviewed in the United States on August 5, 2026 by Marilyn. Newton

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