K9 Advantix II for Dogs 4-Month Supply

Regularly: $67.99
Today's savings: 28%

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In Stock. Usually Ships within 24 hours.



In Stock. Usually Ships within 24 hours.



In Stock. Usually Ships within 24 hours.

Over 55lb


In Stock. Usually Ships within 24 hours.

Shipping weight = 0.10 lb.


Product Summary:

K9 Advantix II Dog: 4-Month Supply

K9 Advantix II delivers pest protection through topical action. It protects against fleas (flea eggs and larvae), ticks, mosquitoes, biting flies, and lice. It combines imidacloprid and permethrin with insect growth regulator pyriproxyfen, which interferes with the hormone signaling of molting insects so that fleas in immature stages are unable to molt. K9 Advantix II is for monthly use on puppie as young as 7 weeks old and dogs. Do not use on cats.

  • Repels and kills ticks, fleas, and mosquitoes
  • Repels biting flies
  • Kills lice
  • Kills all life stages of fleas
  • Prevents development of fleas, flea eggs, and larvae
  • Kills fleas within 12 hours of initial application
  • Kills reinfesting fleas within 2 hours
  • Protects against ticks that may transmit organisms that can cause Lyme disease, Rocky Mountain spotted fever, Ehrlichiosis, and Anaplasmosis
  • Waterproof: continues to work after a bath or weekly swimming (for optimal results, use a non-detergent shampoo)
  • One application lasts for a month
  • Can be used on puppies as young as 7 weeks old
  • Easy-to-follow application instructions on the back of every package
Item Specifications:

4-10 lb.: Green
11-20 lb.: Teal
21-55 lb.: Red
Over 55 lb.: Blue

Includes four applicators

Apply the entire contents of the tube evenly to two to three spots on the top of the back from the shoulder to the base of the tail. Monthly application.

Length of Effectiveness:
Under normal conditions, the product is effective for a 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 (7) days. After flea control is attained, return to a monthly retreatment schedule.

8.80% Imidacloprid
44.00% Permethrin
0.44% Pyriproxyfen
46.76% other ingredients
Active ingredients work synergistically. The combination of imidacloprid with permethrin exerts a unique synergistic effect on the arthropod nervous system that is greater than either ingredient alone. Each compound acts on a different receptor area of the nerve cell:

  • Imidacloprid: (nicotinic receptors) irreversibly opens nicotinic receptors on postsynaptic neurons, resulting in constant neuromuscular stimulation, spastic paralysis, and death
  • Permethrin: (sodium channels) causes prolonged sodium ion exchange across neuronal membranes, resulting in constant nerve discharge followed by spastic paralysis and death
  • When both ingredients are combined, the neurotoxic stimulation is greater than that seen with either ingredient alone
Downloadable Resources
Comparison ChartK9 Advantix II vs Frontline Plus
MSDSK9 Advantix II
Style Item Number Model Number UPC
4-10lb 405588 001 5420348 724089203489
11-20lb 405588 002 5420372 724089203724
21-55lb 405588 003 5420399 724089203991
Over 55lb 405588 004 5420410 724089204103

Product Reviews by Customers

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Browse 1 question Browse 1 question and 50 answers
Why did you choose this?
1800PetSupplies.com Store
I'm been use it since my dog was 11 months old, he is now 4 years and a half. It's a great product.
Arianna R on Nov 13, 2018
seems to work and affordable
becky j on Jun 3, 2018
I'm been use it since my dog was 11 months old, he is now 4 years and a half. It's a great product.
Arianna R on Nov 13, 2018
i have 2 large dogs and it works
Tamara P on Jul 17, 2018
seems to work and affordable
becky j on Jun 3, 2018
I have two dogs that weigh about 52 lbs each and have been using this product for many years with success.
marie d on May 14, 2018
used it before and am satisfied with the product.
B R on Apr 13, 2018
My dog needs it.
frances n on Apr 9, 2018
Recommended by our vet.
Roger M on Feb 10, 2018
I have tried several different brands of flea medications and Advantix II works the best!
Susan W on Dec 9, 2017
price and value
Jenny H on Nov 4, 2017
ran out
Nicole R on Aug 23, 2017
Cheap prices and good service
Shannon A on May 30, 2017
reasonable price!
caitlin h on Apr 20, 2017
because it works!
LINDA K on Apr 7, 2017
use this all the time. works great
Brenda M on Apr 5, 2017
preferred by my vet for my dog
andrea m on Mar 13, 2017
excellent product, easy to apply
Edith G on Mar 11, 2017
Georgina F on Mar 10, 2017
I have always used Advantage and decided to use K9 Advantix II since I read it takes care of mosquitos as well as fleas.
Shari W on Nov 6, 2016
I love K9 Advantix for dogs. It not only kills Fleas, lavas, biting flies,it kills mosquitoes. Mosquitoes can be deadly to our furry friends just like humans. I highly recommend K9 Advantix for dogs or cats.
Hallie J on Oct 13, 2016
I have always used K9 Advantix11 will not change It is the best product to control ticks and fleas where I live.
Lawana C on Aug 1, 2016
It works the best.
Rebecca W on Jul 5, 2016
We live in an area with biting flies and mosquitoes I needed a product that not only killed fleas but also repelled other biting bugs.
Yvonne B on Jul 2, 2016
I've previously used Frontline, and it didn't prevent ticks. Trying this product, and hoping it's better. Read reviews, and liked that it should help with mosquitoes and flies, too. Will review later this Summer.
Jill H on May 11, 2016
KIM on Apr 29, 2016
I chose this because it was highly reccommend by other users I know.
debbie c on Mar 17, 2016
Have used this for years and it works
Denise M on Nov 8, 2015
It works well.
Ronald L on Oct 26, 2015
Frontline wasn't working, this was recommended to me by Petco as more effective so I'm trying it
DAWN J on Sep 26, 2015
"because thats what i used last time and worked well."
LAURENE F on Sep 22, 2015
It is the only flee med that does the job
Mary S on Sep 7, 2015
Cheaper than the Vet's office and quick delivery...
patricia l on Aug 3, 2015
AdvantixII is all I ever use on my pets.
SHERRY E on Aug 1, 2015
$10 off coupon from another site ans I needed the product
Tuesday F on Jul 24, 2015
Suggested by veterinarian because I live in a heavily wooded area. Best protection for ticks.
Karen K on Jun 25, 2015
I have used this product for a while now. I have found it to be wonderful and works great on all my babies. I would highly recommend this product to anyone.
Cynthia R on Jun 22, 2015
Seems like it works better than Frontline Plus....
Retha H on Jun 22, 2015
idaearle on May 31, 2015
Value and effectiveness
Wendy B on May 18, 2015
Because it fights mosquitoes which none of the others do
Amanda m on May 17, 2015
This brand works the best, 1800PetSupplies had the best price and cash back when you shop through Ebates. Win, win, win!!!
Shari A on May 12, 2015
SANDRA B on Apr 28, 2015
Her vet prescribes it
SUE D on Dec 2, 2014
Maryella W on Nov 14, 2014
Dog has fleas & ticks
Aundrea B on Oct 21, 2014
I feel this is a good product, I've used it before and the price is very good on this web site
Suzanne M on Oct 11, 2014
Always have good experience with this product !!!
Carey on Oct 8, 2014
Have had great results with this product, better than <br />Frontline.
Lori S on Oct 5, 2014
very good price for this item
THERESA J on Sep 13, 2014
It works very well.
Denise D on Sep 8, 2014
This works wonderful in the south...my dogs never get fleas
Connie C on Aug 27, 2014
i have 2 large dogs and it works
Tamara P on Jul 17, 2018
I have two dogs that weigh about 52 lbs each and have been using this product for many years with success.
marie d on May 14, 2018