• 12 MONTH K9 Advantix II RED for Large Dogs (21-55 lbs)

12 MONTH K9 Advantix II RED for Large Dogs (21-55 lbs)

Regular Price: $200.99Sale Price: $148.95
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K9 Advantix II RED for Large Dogs 21-55 lbs

Keep your dog safe from irritating and dangerous pests with k9 Advantix for dogs 21-55 Lbs. Formulated for dogs seven weeks of age and older and weighing 21-55 pounds and under, K9 Advantix II outperforms its competitors not only by killing more varieties of pests, but also by repelling them to prevent future attacks.

Repels and Kills Ticks, Fleas, and Mosquitos

The active ingredients in K9 Advantix II help keep your dog safe from ticks, fleas, and mosquitoes. These effective compounds attack the pests' nerve cells, paralyzing and effectively killing them, as well as repelling them from future attacks. Most ticks are repelled and killed before they can attach, which may reduce the risk of transmitting disease-causing organisms to your pet. K9 Advantix II effectively kills and repels Deer ticks, American dog ticks, Brown dog ticks, and Lone Star ticks.

K9 Advantix II for Large Dogs up to 21-55 lbs
  • Kills and repels ticks, fleas, and mosquitoes
  • Repels biting flies and kills lice
  • Waterproof formula won't wash off from swimming or bathing
  • Includes twelve convenient one-month doses
  • Easy to apply
  • For dogs seven weeks of age and older and weighing 21-55 pounds and under
  • Per Dose: $10.92
Dog flea life cycle
K9 Advantix II and Frontline Plus Comparison Chart
Fights Against Fleas at All Stages of Development

K9 Advantix II protects your pet against fleas at all stages of the parasite's development. K9 Advantix II breaks the flea life cycle by killing the living fleas on your dog before they can lay eggs. It also prevents the development of existing flea eggs, larvae, and pupae, helping to prevent future infestations.

K9 Advantix II also kills reinfesting fleas (newly hatched fleas jumping back on your dog) within two hours, and it prevents fleas on a treated dog from infesting your home.

Effective Against Biting Flies and Lice

In addition to complete tick, flea, and mosquito protection, K9 Advantix II also repels painful biting flies from feeding on your dog, and it effectively kills up to 100 percent of lice within one week of treatment.

Waterproof Formula

K9 Advantix II is waterproof, so there's no need to reapply after your dog has a bath or goes for a swim. Studies show that dogs are still protected against parasites after exposure to water, though for best results, dogs treated with K9 Advantix II should be bathed with a non-detergent shampoo.

Package Contents

2 Boxes includes six 2.5-milliliter tubes of K9 Advantix II for Large Dogs 21-55 pounds.

Flea Cycle

Usage Info

How to Apply

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, retreatment 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 retreatment 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.



How long does K9 Advantix last?

A single application of K9 Advantix keeps working for one month.

How often should I use K9 Advantix?

Experts recommend monthly application to keep your dog protected year-round.

My dog is strictly indoors. Should I still use K9 Advantix?

Yes, ticks and fleas can be brought into the home by people or other pets--without owners even realizing it. Immature flea stages remain dormant until conditions are appropriate for development. This is why it is also important to protect indoor pets.

Can I bathe my dog during the month after application?

Yes, you can give your dog a bath. A non-detergent shampoo is recommended for best results.

How young can the dog be for application?

K9 Advantix is gentle enough for puppies as young as seven weeks.




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.


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 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.


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 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.


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 reinfestation.

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%
*cis/trans ratio: max 55% () csi and min 45% () trans
Net Contents

Twelve tubes, each 0.084 fluid ounces (2.5 milliliters)

4 MONTH K9 Advantix II RED for Large Dogs (21-55 lbs)4 Mo K9 Advantix II (21-55 lbs)Reg price: $71.99
Sale price: $49.95
6 MONTH K9 Advantix II RED for Large Dogs (21-55 lbs)6mo Lrg Dog (21-55lb) K9 Advantix 2Reg price: $101.99
Sale price: $74.95
4 MONTH K9 Advantix II BLUE for Extra Large Dogs (over 55 lbs)4 Mo K9 Advantix II (55+ lbs)Reg price: $72.99
Sale price: $49.95
6 MONTH K9 Advantix II BLUE for Extra Large Dogs (over 55 lbs)6mo XLrg Dog (55lb+) K9 Advantix 2Reg price: $102.99
Sale price: $74.95
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Customer Reviews

DISCLAIMER: The results described on the testimonials on this site, are the individual experiences and personal opinions of those who have purchased and used the products. These testimonials are not intended to make any claims that the products can be used to diagnose, treat, mitigate, cure or prevent any disease or medical condition.
Click here to see all reviews
Great Prices on Advantix by Mrs. P from Danville, CA12/11/2011

Great prices found here! Love this website for flee/tick medicine for my two pugs!

Great Price and Great Product by sgervaismesasavage from raleigh, nc06/30/2012

I love K9 Advantix II. Ive used Frontline in the past for years but never realized that it didnt repel and kill mosquitos or biting flies. I switched to K9 Advantix II and am extremely pleased. Even better is when I found this site which sells the products for the best price!

by Dogfriend06/19/2014

This product performs better than Frontline but still lacks the ability to kill fleas for 30 days. My dogs still get fleas on them that this product does not kill. Have to supplement with Capstar. Do not like it being oil based instead of water based. Be careful of staining your furniture until product completely dries on your dog.

K9 Advantix by garya05/21/2014

Best price I could find on line and fast shipping. Will use again for more supplies.

by Leslie12/24/2012

Good product for fleas, etc., and it doesn't cost as much as if you purchased it at the vet's.

Works the Best.. by Frenchiemom2 from Pittsburgh, PA05/30/2012

I was using another brand on my dogs to try and save money. I found a tick on my dog and panicked because if I was using K9 Advantix II, I wouldn't have had to worry. So I switched back immediately...

Solved Flea Problem by Cece02/06/2013

Unexpectedly got a flea problem in the house. This product with vacuuming and washing insures control of any remaining pupae emergence with life cycle control.

Advantix for tick/flea protection by Barry from Southern Maryland01/08/2013

This product generally works well. Easy to apply. During the height of tick season, I might still find an occassional tick on our dog. Most often, the tick s aleady dead or dying. Not always though which may mean the tick has not been on our dog long enough for the medicine to have killed the tick. An ideal product of this nature would stop ticks from even alighting or staying on the dog, but perhaps that is asking too much,

Excellent Value by rich from Michigan04/02/2014

This is a very good product. I want to keep my dog protected.

Helped our dogs get rid of fleas by Sage from Grand Rapids, MI12/07/2012

I didn't realize our 17 year old dog had fleas, but when I saw the little black specs I realized she needed help. So I purchased the Advantix and it did help kill the fleas and I do not see black specs on her any more.

Excellent Product by Mark from Clifton, Virginia01/12/2013

We have been using Advantix for our 5 dogs for several years - in that time they had no ticks or any other parasite. It works.

great product by dog rescuer from Riverside County, Calif.06/26/2012

we have few problems with fleas/ticks, but with dogs who are "dumped" in the area, they need protection from re-infestation and find that this preventive approach is easy and works. I automatically use the product when a new dog is brought onto the property.

Great Deal & Great Product by Cocker Spaniel Fanatic from Pennsylvania01/06/2013

Having four cocker spaniels, I am always looking for the most economical way to care for my furry friends. Entirely Pets allows me to do so with top-of-the-line products! K9 Advantix II is highly effective. I have not found a flea or tick on any of my dogs since I've started using it. I am extremely happy with this product and will continue to purchase it.

excellent product by Ellen from Buzzards Bay,Ma11/06/2012

wonderful product: no fleas or ticks, ever! And mosquitos leave our guys alone as well: would be nice to have such effective product for humans.

Good product at Great Price by camb53 from Alabama07/16/2012

Keeps fleas and ticks off my two dogs and no adverse reactions for either of them.

Good stuff by Butchy's mom from Pacific Northwest11/03/2012

I've been using this product for a couple of years. Haven't seen even one flea. My dog doen't seem to mind the drops even though he has hated others.

Great for repeling mosquitos, fleas and ticks by Pat V from Scotia, NY07/07/2013

Nothing better to keeping the dogs free of nasty parasites.

Effective by Christine from Sterling, Ma06/20/2013

I love this product. I have used it for years and will continue to do so. Entirely Pets is very cost comparitive as well....best place to shop for your pets supplies and needs.

Great Stuff! by CharlieHonse from Greensburg, PA05/30/2013

I have three labs and do not wants an infestation of fleas in my home or yard. We also have two cats, that never go outside, so if the dogs don't bring them in the cats can't get them! I put a reminder on my iPhone to email me a message to remind me to apply once a month! We have had not fleas, ticks or lice in our home and or on my pets!



Best Flea and Tick Product for Dogs by Tony and Ruth08/07/2014

We have tried cheaper products to control flea and ticks on our 4 dogs, but we have come back to this product because it is the only one that works for us. We also find the price to be very good and auto delivery perfect for us.

comfort for dog by lv from NC03/17/2013

I used to use Frontline Plus for my dog and it worked just fine but we are in an area that has lots of mosquitos so i switched to Advantix and it seems to work as well as the other. I will keep using it.

Does the job! by peg04/01/2013

I've been using this for quite some time and find it does what it is designed to do--kill fleas and ticks.

great product by Ronda03/30/2012

I have had as many as six dogs at a time. For years now I have been using this product It has never been a problem. No fleas, ticks or mosquitoes. No trying to get dogs to eat a pill . The only thing I would change is the packaging For old hands sometimes it is hard to get the little tubes out of the plastic, foil packages.

K9 Advantix II by Karen from VT06/26/2013

This product is great- HOWEVER, the recommended dosing causes neurological issues in ALL four of my dogs. I have to buy the size rated for the next one down. For example, if my dogs weigh 40 lbs, which they all do plus or minus a pound or two, I should be buying the LARGE dog 21-55 lbs. This is too much for them and I've heard this from many family members also and they buy the next size down, which is medium 11-20 lbs. Maybe they need to relabel these since last I knew, forty pound dogs arent large anyway, to me a large dog would be a pitbull or german shepard or something.

No fleas - no ticks - no worries by Littlebird from Welcome, Texas03/07/2012

This is the best product I have ever used to preventive fleas and especially ticks from feasting on my dog. She is highly allergic to fleas and since using this product, have had NO issues with itching or "hot spots". Also, no more worries of her getting ticks. We live in the country with lots of deer and other carriers and I no longer have to worry about a tick problem!!! Thanks for the great product!!!!!

Giving it a Try !!! by Petlovertoo03/11/2012

I previously used Frontiline Plus on my dogs. Over the past year I have found it not to be as effective on fleas and ticks. Since we had such a mild winter, fleas and ticks will be rampant, so I switched to Advantix II in hopes of getting much better results.

Works without burning by Hanz' girl friday from San Antonio Tx12/01/2011

OK..so like everyone says things work well but this one has worked for us for many years...like about 8 years...switched to this as it covered ticks much better than other brands AND no site burning or hair loss. When I used another brand my dogs would go nuts trying to get rid of the burn at the multiple sites of application...plus we would still be picking off ticks...We feel confident with the use of this product

does a great job on ticks by djw06/28/2012

I've been using this product for years, it does a great job keeping our dogs tick free.

K9 Advantix by Dani from Phoenix, Alzheimer's06/11/2012

I use this product every summer for several months on 6dogs. One of my girls is very sensitive to anything she comes into contact with, she handles this AdvantixI with no problem. It's the only flea and tick product that I will use on my pets.

only product i would purchase by sheila from gainesville ga10/31/2012

i have ordered advantix ll the last 2 years, it has repelled ticks 7 fleas. i have not had any problems & we hike regularly.

advantix ll by pugsgoofy from Stroudsburg, PA06/01/2012

I have used advantix for years. I like it because it is topical. Frontline absorbs in the bloodstream. I do not like frontline for that reason. I do not put unnecessary chemicals on my dogs. The only issue I have with my order of Advantix ll is it does not seem to have an expiration date on it only lot numbers. Therefore, I do not know how old it is.

When top spot became less effective... by Barb from Virginia03/11/2013

I switched to K-9 Advantix when Top spot became less effective. Over time, many products can lose their effectiveness and it is good to know their are others that can be used just as well.

K9 advantix II by KinPA from The Poconos, PA12/18/2012

I just love this product. I prefer it over the Frontline Plus. Keeps the fleas etc. off the dog. Great product.

best flea & tick product by Margie from Gloucester, VA07/03/2012

I have not seen a tick or flea since using this product.

On-going best deal by Fritz from NC04/21/2014

I have used Entirely Pets over the last several years and they continue to be the best deal out there, both in pricing and the speed of shipments!

Advantix by Guiness01/23/2013

Product great Price the best anywhere Service and delivery great

Dog itched by Vince from MA11/28/2011

I have a 35 lbs Minature Aussie. We have had good luck with the origional K9 Advantix, but this new Advantix II, my dog was very upset with. He itched for days and was very unsettled. I am afraid to use the rest.

by RGS07/31/2012

This product works great for flea/tick/mosquito prevention. We live in the south so we need to use this product year round. It was recommended by our vet since other products don't provide as much protection against "varmints." Plus, this is a good value and always arrives promptly.

Will never change.......... by Lynn from Knoxville, TN.11/14/2012

I have been using this product on my dogs for many years. I would never use anything else. My oldest dog was born with renal disease. She is now eleven and I have always used this product on her. If it is safe for her, does what it's suppose to do, why change.

Great protection by Cooch from Pepperell, MA05/25/2014

I haven't seen a flea or tick on my dog since I started using Advantix II.

best so far by diana from new jersey, new york upstate07/20/2012

we have 7 dogs. only product where we haven't had any ticks brought into house.

Great Product by Teddysmom from Phoenix, AZ05/30/2012

I've been using Advantix on my dogs for many years. It's a great product. I've never seen a flea or tick on my dogs when this product has been used. Entirely Pets is fantastic - I couldn't believe how fast my order arrived with standard shipping!

Prompt Service by GA Peach from Macon, GA06/15/2012

EntirelyPets processed our order for K9 Advantix II promptly and correctly and we received the product quicker than anticipated so that our doggies got their doses on time!

by Randy from Tennessee04/17/2012

Fast free delivery. Good price. Happy with our order.

by adevilbiss11/11/2012

Best prices around. Always works great for my 2 dogs.

Great for tick and flea prevention by pippalou from TN04/04/2014

I started using K9 Advantix a couple of years ago. My dogs are out in the woods a lot, so they tend to be where ticks are, and our previous tick treatment didn't seem to work so well. I changed to K9 Advantix, and it worked much better at keeping the ticks off. I highly recommend it for ticks and fleas.

by from 07/03/2012

I have searched all websites of flea protection and Entirely Pets has the BEST prices!

Pam by from Pam

Great product


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