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K9 Advantix II for Dogs 2-Month Supply

Regularly: $39.99
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 = 0.50 lb.


Product Summary:

K9 Advantix II Dog: 2-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 puppies (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 two hours
  • Protects against ticks that may transmit organisms that can cause Lyme disease, Rocky Mountain spotted fever, Ehrlichiosis, 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 2 applicators

Apply entire contents of 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 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 405587 001 5406055 724089060556
11-20lb 405587 002 5406063 724089060631
21-55lb 405587 003 5406071 724089060716
Over 55lb 405587 004 5406098 724089060983

Product Reviews by Customers

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Browse 4 questions Browse 4 questions and 51 answers
Why did you choose this? Store
The vet highly recommended this brand.
MICHIKO N on Oct 21, 2018
Googled & was highly recommended plus fits weight class for majority of our dogs--price was good
sharon d on Aug 7, 2018
The vet highly recommended this brand.
MICHIKO N on Oct 21, 2018
Works great and my two lab mixes have no side effects from it.
Debra H on Oct 2, 2018
Googled & was highly recommended plus fits weight class for majority of our dogs--price was good
sharon d on Aug 7, 2018
works well on my large outside dogs
Leanna B on Jul 20, 2017
I'm not sure if this will work on my dog to repel fleas but am grateful that I could get a 2 month supply to try it. My dog is allergic to fleas so it's important that the repellent factor work. If it does, I'll purchase a four month supply.
Linda G on May 18, 2017
our dogs have all done well with this flea adverse reactions and no fleas!
Direct C on May 10, 2017
Good reviews, referral from a friend.
Barbara R on Feb 6, 2017
vet recommended
Howard E on Nov 14, 2016
I've heard great things about this product. I applied it and both dogs had reactions it was awful. This product wasn't good for my dogs.
Terekah T on Nov 13, 2016
Woks to keep my dog save.
LAURI M on Oct 12, 2016
It seems to be the best at this time for my little ones.
KELLIE J on Sep 17, 2016
Been using this product for months now. It is a brand I trust and know for a fact that it works as advertised.
MELISSA C on Sep 14, 2016
works great
sue s on Aug 4, 2016
K9 Advantix ll is the only flea spot on that truly works! The fleas don't have to bite my dog to be killed...
Susan K on Jul 21, 2016
i have used this product before and i like it better than frontline.
janice b on May 11, 2016
Never used it before want to see if it really works
Elisa G on May 8, 2016
Works quickly and last
Judy B on May 2, 2016
The flea medicine we have been using from our vet isn't working. I have tried this in the past and it seemed to work so I decided to return to it.
Carrie M on Apr 23, 2016
needed item
Jim S on Feb 16, 2016
Advantix II works wonders!
Emily C on Dec 31, 2015
Frontline hasn't been working so I wanted to give Advantix a shot, since it has worked better for me in the past. None of the vets around here carry it, just Frontline. This site had the best price on Advantix, plus the option of a 2-month supply rather than 4 or 6 months and free shipping. Hopefully, this will take care of the fleas.
Staci C on Dec 8, 2015
It works.
Joyce R on Oct 30, 2015
like the product
Linda C on Oct 16, 2015
just need a couple to get through.
Gillian T on Sep 22, 2015
They work
Cristina M on Sep 21, 2015
I have used this on my little beagle for years and it works!
KATHLEEN E on Sep 18, 2015
best price for product I've found anywhere!
AMI S on Aug 4, 2015
Fleas and ticks are not bad in my neighborhood
Alisha B on Jun 20, 2015
Great product for flea and tick prevention
Claudia S on May 13, 2015
best flea and tick meds for my three dogs always works!
Kathleen R on May 3, 2015
SLHARNER S on Apr 14, 2015
Good reputation and good reviews.
CHRISTINE M on Apr 8, 2015
it works
LINDA D on Apr 3, 2015
used before and works
Cheryl K on Apr 2, 2015
Used before, works well for outside dogs
Bobbi B on Mar 23, 2015
It is a very dependable product
Sharon P on Dec 20, 2014
From all the other brands for Fea protection for my dogs this one works the best
JACQUELYN W on Nov 19, 2014
For the price and no shipping fee
Yvonne S on Nov 12, 2014
The internal medicines make my dogs sick and I don't like giving them poison. I read good reviews about this product. We shall see...
Christy S on Oct 10, 2014
it works
Judy G on Oct 9, 2014
this item works, and the price is right.
GLENN O on Sep 19, 2014
It really works for fleas and ticks. Front line does not compare.
REBECCA K on Jul 30, 2014
Great product...never fails
HEATHER S on Jul 2, 2014
to prevent fleas
Tiffany T on Jun 8, 2014
it works
kathy w on Jun 3, 2014
It's the best. I've tried several different flea and tick repellents and this one works the best.
AMANDA B on May 9, 2014
Works great and my two lab mixes have no side effects from it.
Debra H on Oct 2, 2018
works well on my large outside dogs
Leanna B on Jul 20, 2017
is this ok if I have cats?
Rich R on Dec 26, 2014
BEST ANSWER: Putting this product on your dog, as instructed, will not harm your cat. We have a cat in the house..and she did not have any problems with the treated dogs. Please be certain to never apply the K9 application to your cat as this will have a harmful effect.
safe for breeding dogs?
A shopper on Dec 18, 2017
BEST ANSWER: Per the manufacturer it is safe on dogs and puppies 7 weeks and up, but you should consult your Veterinarian for pregnant or lactating mothers.
My dog weighs 176 pounds as of his 1 year rabies shot at the vet last month. I see that the highest weight is "over 55 lbs"
Will it work for my dogs or do I need something else?
Karen C on Jul 22, 2014