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4 MONTH K9 Advantix II BLUE for Extra Large Dogs (over 55 lbs) Video

4 MONTH K9 Advantix II BLUE for Extra Large Dogs (over 55 lbs)

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K9 Advantix II is one of the top choices for eliminating the resident tick or flea population. It is manufactured by Bayer, one of the leading pet care companies in the world. This product promises to kill and repel ticks, fleas, and mosquitoes. Its waterproof formulation remains effective even after the pet gets wet. The K9 Advantix II solution works by attacking all the life stages of the parasites killing adult bugs, larvae, and eggs. The K9 Advantix II Blue is a specialized product for extra large dogs weighing over 55 lbs. This particular pack contains 4 doses, which is good for 4 months of protection against ticks and fleas.

  • For extra large dogs weighing over 55 lbs
  • Manufactured by Bayer
  • Waterproof formulation
  • Repels ticks, fleas and mosquitoes
  • Kill parasites of all life stages
  • For dogs only


Imidacloprid: Imidacloprid is an ectoparasiticide, an antiparasitic agent that targets parasites living primarily on the surface of a host. Chemically classified as a chloronicotinyl nitroguanidine, imidacloprid inhibits neurotransmitter transmission in insects, resulting in paralysis and death.

Benefits: Imidacloprid exhibits both adulticide and larvicidal flea efficacy; it not only kills adult fleas and larvae on your pet, but it also kills larval stages in your pet's immediate surroundings.

Main Purpose: To kill fleas at all stages of their life cycles and stop them from being able to move or feed.

Permethrin: Permethrin is the additional ingredient in Advantix. It belongs to the Type I class of pyrethroid acaricides and insecticides, and it also acts as a repellent. Pyrethroids affect muscle and nerve cells' sodium ion channels by increasing their mean open time, which leads to hyperexcitability and death of the parasite.

Benefits: Thanks to its repelling activity, permethrin reduces parasite bites and thus the risk of diseases and stress for your dog.

Main Purpose: To repel ticks, sand flies, and mosquitoes; to kill ticks and fleas.

Two Proven Ingredients with Enhanced Activity: Imidacloprid and permethrin work together to overwhelm the nervous system of the parasite, providing neurotoxic activity beyond that of each compound alone. This leads to more profound and quicker insect paralysis and death.

Specifically, imidacloprid increases the efficacy of permethrin by activating insect nerve cells and increasing the frequency of neurotransmissions. As a result, more sodium channels are opened and the pyrethroid can interact much better with its target site.

Pyriproxyfen: Pyriproxyfen is a pyridine-based pesticide. A juvenile hormone analog, it interferes with the hormone signaling of growing insects, so that insects in immature stages are unable to mature. Additionally, a female insect that touches the toxin will produce eggs that will not hatch.

Benefits: Pyriproxyfen provides an added layer of protection for pets and their surroundings. It interrupts the flea life cycle at multiple stages, halting the growth and development of insect eggs and larvae and preventing re-infestation.

Main Purpose: To prevent flea eggs from hatching and larvae from growing.

Active Ingredients % by Weight
Imidacloprid 8.80%
Permethrin* 44.00%
Pyriproxyfen 0.44%
Other Ingredients 46.76%
Total 100%

Useful Information

Applying K9 Advantix II to your pet is a fast and easy process. First, remove the K9 Advantix II applicator tube from its packaging and use scissors to peel down the foil. Next, hold the applicator tube in an upright position and pull the cap off the tube. Use the upturned cap to break the protective seal, and you're ready for application.

For easiest application, your dog should be standing upright. Evenly apply the entire contents of the K9 Advantix II tube to two or three spots from the back of the shoulder to the base of the tail. Part the hair at each spot until the skin is visible, then place the tip of the tube on the skin and gently squeeze out a portion of the solution. Be careful not to apply an excessive amount of the solution in any one spot, otherwise some of the solution might run off the side of your dog. Dispose of the container and do not reuse or refill. Do not empty unused product in any indoor or outdoor drain.

For optimal control and prevention of parasites, use K9 Advantix II every month. K9 Advantix II is available in four- and six-month supplies. Do not use K9 Advantix II on cats or any animals other than dogs.

Application Instructions: Evenly apply the entire contents of the tube to four to six spots on the top of the back--from the shoulder to the base of the tail. Apply monthly.

Length of Effectiveness: Under normal conditions, the product is effective for one month. However, in cases of severe flea infestation, re-treatment may be necessary earlier than four weeks. Do not retreat more often than once every seven days. After flea control is attained, return to a monthly re-treatment schedule.

Hazards to Humans: Causes eye irritation. Harmful if swallowed. Do not get in eyes or on clothing. Avoid contact with skin. Wash hands thoroughly with soap and warm water after handling.

Hazards to Domestic Animals:

*For external use on dogs only. *Do NOT use on animals other than dogs. *Do NOT use on puppies under seven weeks of age.

Do not get this product on dog's eyes or mouth. Consult your veterinarian before using this product on debilitated, aged, pregnant, or nursing animals. Individual sensitivities, while rare, may occur after using any pesticide product for pets. If signs persist, or become more severe, consult a veterinarian immediately. If your animal is on medication, consult your veterinarian before using this product.

Do Not Use on Cats: Due to their unique physiology and inability to metabolize certain compounds, cats must not use this product. If applied to a cat, or ingested by a cat that actively grooms a recently treated dog, this product may have serious harmful effects. If this occurs, contact your veterinarian immediately.

Environmental Hazards: This product is extremely toxic to fish. Do not add directly to water. Do not contaminate water when disposing of product or package.

    First Aid: Have the product container or label with you when calling a poison control center or doctor, or when going for treatment.

    If in eyes: Hold eye open and rinse slowly and gently with water for 15 to 20 minutes. Remove contact lenses, if present, after the first 5 minutes, then continue rinsing eye. Call a poison control center or doctor for treatment advice.

    If swallowed: Call poison control center or doctor immediately for treatment advice. Have person sip a class of water if able to swallow. Do not induce vomiting unless told to do so by the poison control center or doctor. Do not give anything by mouth to an unconscious person.

    If on skin or clothing: Take off contaminated clothing. Rinse skin immediately with plenty of water for 15 to 20 minutes. Call a poison control center or doctor for treatment advice.

    To physician: Treat patient symptomatically.

Keep out of reach of children.

Customer Reviews

58 Reviews
81% (47)
7% (4)
7% (4)
2% (1)
3% (2)
91% Recommend this product (53 of 58 responses)
By ToriaGold
December 31, 2018
Good quality product that I've used for years
I started using K9 Advantix II about 5 years ago, and have been very satisfied with it. I was previously using Frontline for over 10 years, but switched to K9 Advantix II when my vet told me that it prevents and treats more things than Frontline does. It is also a little less expensive too! I've attached a comparison chart of the two products.
By kittenonkeys
Central Louisiana
August 12, 2017
K9 Advantix II
I've been using this product for several years now, and my pets have no problems with fleas or ticks. I highly recommend it.
By DogMom
Indianapolis, IN
June 18, 2017
Won't use anything else
We have always had great success with using Advantix. I love that it also repels mosquitoes. We just returned from a weekend of camping deep in the woods with our dog with no problems keeping the bugs away. He is a happy pup!
By Hun
June 3, 2017
Best flea/tic protection
We live in the woods with lots of deer & squirrels, etc., and this has been the best protection we have found for our dogs in preventing fleas & tics. Easy and effective.
By Afghan m.
Columbus, OH
August 14, 2016
really works well
In addition to the flea and tick protection, this product repels mosquitos - a little additional protection against bug-born illnesses. The only negative is that the product is really greasy, and makes a mess wherever the dog lays down. The manufacturer told me that the day after application, the dog's back can be wiped down to relieve this messy business. But it means no petting or snuggling for several days.
By RaquelD
Washington State
June 22, 2016
Long Time Consumer
Been using this product for years on my GSD and never had a problem with fleas!
By Mist
Albuquerque NM
April 24, 2016
Great Product
This is my second year of using this produce and find it to be the safest for my pet. It achieves more than most of the other products on market.
By bkliche
Colorado Springs, CO
August 31, 2015
Easy to use
Of course it came with detailed instructions but the applicator was easy to open and easy to use--didn't have to mess with scissors or a knife.
By Marty
August 25, 2015
Have used for years
This has been great for all of my dogs. They have never had fleas and seldom had any ticks. My dogs are all working dogs, so I use it year long. The price is probably the best, especially if you have multiple dogs.
By Rick
Central Pennsylvania
May 31, 2015
Works Good On My Wife's Boxer
We live in the woods & been buying this item for the past 7 years & it works good with a Preventic tick collar also.
By Susan
April 7, 2015
Products does it's job.
This products works as it should. We walk in the woods all the time and no ticks or evidence of Lyme's disease. Never had fleas either.
By Gitanjali
February 7, 2015
Weight range
This says it is for extra large dogs over 55lbs. My great danes are over 100lbs. I use it on them. But I do have to use other sprays in their room to have total tick control. I wish they would have tubes for every 10lb of body weight like they do for de-worming tablets. That way a precise dose can be worked out for each dog.
By marty
August 15, 2014
4 month k9 advantix 11
I am not sure that there was anything in the tube. The dog felt dry after the application.
By Lin
Hollis, Prince of Wales Island, Alaska
July 5, 2014
This is The Best protection product!
I have been using K9Advantix since it first came out, for my Newfoundland dogs. Here where we live in Alaska, we do not have a flea or tick problem but we have a huge issue with mosquitoes, no-see-ums and aweful biting flies of all sizes which will drive human and animal alike, crazy with their painful bites. K9Advantix are the only drops I have found to work effectively against these biting critters and most drops only guard against fleas and ticks. Great product!!
When I moved to Alaska, I discovered that no companies would ship it here. Then I discovered EntirelyPets and after one conversation I learned that they would indeed ship to Alaska. I was skeptical but they did it...and quicker than we usually get things. I am a fan of EntirelyPets and a lifetime user of K9 Advantix!
By Angel
Providence, RI
May 9, 2014
Great product
I am happy with this product. I previously purchased Front Line, I was satisfied with this product also. However, my veterinarian dermatologist recently advised me to switch to Advantix II.
By KShep
Turnersville, NJ
May 1, 2014
Best price for best product of this kind. Used on 84 lb. German Shepherd.
By ErinE
Tucson, Az
November 27, 2013
Disappointing results
We have four large dogs who suddenly had ticks. We have used the Advantix II for three months and are still finding live ticks on the dogs...First we washed the dogs with a tick/flea shampoo, sprayed the yard every 3 weeks, washed all bedding, and vacuumed.
I would not recommend this product to anyone.
By Angie
November 15, 2013
Worked great
After trying numerous products, including Frontline, flea dips,knockout spray, and diatimacious earth, I was ready to tear my hair out. I switched to Advantic and the flea problem was under control within 2 days.
By Kay
Wheeling, WV
November 14, 2013
Super Fast Shipping, Order was Correct, Great Product for my puppy.
By Susan
October 29, 2013
Good product
Seems to work well, still gets the occasional tick but better than other products.
By Debra K.
Lewiston, Maine
August 13, 2013
K9 Advantix ll
This stuff works great, my dogs have had no fleas or ticks or lice this year, works much better than the Frontline Plus I used to use, I will be using this from now on
By bo
South Carolina
August 7, 2013
Great purchase
The flies would bother my lab and this is a great product that keeps them away. It work great for flees and ticks also.
By carebear322
July 29, 2013
Review for 4 MONTH K9 Advantix II BLUE for Extra Large Dogs (over 55 lbs)
Great product. We had previously purchased the leading brand flea & tick medicine and it did not work at all. This started working in the 1st day!
By Carol50
St. Louis, MO
July 11, 2013
Great product & price
We live in St. Louis with lots of fleas, ticks, biting flies, mosquitos, etc. and our poor dog was scratching and itching to the point of sores. I applied the K9 advantix II and within 36 hrs the itching and scratching had stopped. The sores have healed and he's doing great. The product has performed as advertised and is MUCH less expensive than Frontline
By J-Cin
Wilmington, DE
July 10, 2013
Very Good ! !
We know fleas have been bad in our area, but We Have Been Flea Free !
By Lisa M.
July 2, 2013
Review for 4 MONTH K9 Advantix II BLUE for Extra Large Dogs (over 55 lbs)
great and works very well every month!!!
By elemutt
June 13, 2013
Review for 4 MONTH K9 Advantix II BLUE for Extra Large Dogs (over 55 lbs)
This product has worked well on my shepherds.
By Pam
Mooresville, North Carolina
May 20, 2013
Protection at a decent price
Sam's vet prescribed Advantix II and it works great!. The only problem is that the vet is so expensive on the products they sell. Thankfully, I found Entirely Pets and can keep Sam on Advantix for a more reasonable price.
By CandCfam
Tacoma, WA
May 14, 2013
Advantix II seems to be working thus far
The price was right, the shipping very fast, the application easy and seems to be working so far. No complaints!
Bradenton, FL
March 6, 2013
Best flea control for Golden Retrievers
This product has always worked better for me than any other flea control. I tried Frontline when my dog was a pup and it did NOTHING. The Bayer products are the only ones that work. I especially like the fact that they are absorbed and don't leave an oily residue.

Questions and Answers

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6 MONTH K9 Advantix II RED for Large Dogs (21-55 lbs)6 MONTH K9 Advantix II RED for Large Dogs (21-55 lbs)Reg price: $88.99
Sale price: $67.99
12 MONTH K9 Advantix II RED for Large Dogs (21-55 lbs)12 MONTH K9 Advantix II RED for Large Dogs (21-55 lbs)Reg price: $170.99
Sale price: $130.99
6 MONTH K9 Advantix II BLUE for Extra Large Dogs (over 55 lbs)6 MONTH K9 Advantix II BLUE for Extra Large Dogs (over 55 lbs)Reg price: $88.99
Sale price: $67.99
12 MONTH K9 Advantix II BLUE for Extra Large Dogs (over 55 lbs)12 MONTH K9 Advantix II BLUE for Extra Large Dogs (over 55 lbs)Reg price: $170.99
Sale price: $130.99
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