K9 Advantix II Medium Dog Vet-Recommended Flea, Tick & Mosquito Treatment & Prevention | Dogs 11-20 lbs. | 12-Mo Supply
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Availability:
In Stock.
Arrives
Monday, Oct 13
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Style: Medium Dog only
Size: 12 Pack
Features
- Contains one 6-pack, one 4-pack, and one 2-pack of K9 Advantix II for Medium Dogs 11-20 lbs. Do not use on cats.
- 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. K9 Advantix II Medium Dog topical, spot-on formula makes application simple - going on in seconds. You’ll also love that K9 Advantix II is fragrance-free and waterproof after 24 hours of application. K9 Advantix II pest protection is effective on both indoor and outdoor dogs. K9 Advantix II Medium Dog is a trademark of Elanco or its affiliates.
Brand: K9 Advantix
Item Form: Topical
Scent: Unscented
Dog Breed Size: Medium
Date First Available : November 2, 2022
Manufacturer : K9 Advantix
Best Sellers Rank: #357 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 32,052 ratings
Manufacturer: K9 Advantix
Date First Available: November 2, 2022
Brand Name: K9 Advantix
Target Audience Keyword: dogs
Color: Medium Dog only
Size: 12 Pack
Style: Medium Dog only
Frequently asked questions
If you place your order now, the estimated arrival date for this product is:
Monday, Oct 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
Style: Medium Dog Only
Size: 6 Pack
Excellent product that gives me peace of mind that my seven dogs are being protected from hurtful bugs . I love it and will forever order it. Adela
Reviewed in the United States on June 11, 2025 by Adela excellent product
Style: Medium Dog Only
Size: 4 Pack
I have been using this product on my Yorkie for several years. The product works very well. My dog has never had any issues with her skin and no fleas or ticks. I highly recommend it.
Reviewed in the United States on June 1, 2025 by Woodsy
Style: Medium Dog Only
Size: 2 Pack
The item was fine the delivery was delayed the person really was confused I guess anyway thank you for finally getting my package to me
Reviewed in the United States on June 10, 2025 by Nice
Style: Medium Dog Only
Size: 2 Pack
Came very fast. Not sure why my dog still has some fleas. They must be environmental.
Reviewed in the United States on June 9, 2025 by Jennifer
Style: Medium Dog Only
Size: 4 Pack
It's not a name brand but for the last few seasons our puppers (teacup terrier) can roam the yard and comes in tick free
Reviewed in the United States on June 9, 2025 by abriteday
Style: Medium Dog Only
Size: 4 Pack
This stuff has worked on my dogs for years. Love it I’ve never had an issue with it and neither have my fur babies.
Reviewed in the United States on June 5, 2025 by Beverly Pendleton
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.
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Reviewed in the United States on October 15, 2015 by rlbuzz
Style: Medium Dog Only
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.
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Reviewed in the United States on January 11, 2023 by Shauna Cartwright