K9 Advantix Flea, Tick & Mosquito Prevention for Small Dogs, 4-10 lbs, 2-Monthly Treatments

Deal
Skip image gallery
Slide 1 of 10

$9.74 First Time Autoship Price
this order
Save 35% (up to $20) today when you set up Autoship. 
$14.98 Autoship Price
future orders
  • Get deliveries on your schedule
  • Skip, change, or cancel anytime
$14.98 Chewy Price
($7.49 /ea)
Save $0.01
$14.99 List Price
Promo, Spend $100, Get $30 eGift Card with code NEWYEAR
Promo, New Customers Only: Spend $49+, Get $20 eGift Card + Free Shipping with code: WELCOME
In Stock
FREE 1-3 day delivery on first-time orders over $35
Free 365-day returns

No interest if paid in full in 6 months on PayPal purchases of $149+. .

About This Item

Details

  • K9 Advantix for small dogs is ideal for dogs ages seven weeks and older weighing 4–10 pounds.
  • Formulated to protect your pup from fleas, ticks, mosquitoes, biting flies, and lice for 30 days per treatment.
  • Works on contact to kill and repel fleas on dogs within 12 hours of application even without a bite.
  • This easy-to-apply topical treatment is fragrance-free and waterproof after 24 hours.
  • K9 Advantix offers fast relief—no prescription needed.

Ingredient Information

Instructions

K9 Advantix for Dogs

K9 Advantix, from the Advantage brand, prevents and treats fleas, ticks, mosquitoes, biting flies, and lice on dogs. It works through contact to kill fleas on dogs within 12 hours of initial application. Do not use on cats.

One Application Protects for 30 Days

This once-a-month topical flea and tick treatment is easy to apply, and the fragrance-free formula is waterproof after 24 hours of application. Plus, K9 Advantix is available without a prescription, so you don’t have to go to the vet to get it.

How It Works

K9 Advantix kills fleas through contact. It also kills and repels mosquitos and ticks, kills lice, and repels biting flies. Apply K9 Advantix to your dog once every 30 days according to the complete directions for use on the product label.

Find the Right Dose for Your Dog 

Your dog should be at least 7 weeks old to use K9 Advantix. It comes in four sizes, according to your dog's weight: Small Dog (4-10 lbs.), Medium Dog (11-20 lbs.), Large Dog (21-55 lbs.), and Extra-Large Dog (over 55 lbs.). Use as directed by label.

About Advantage

The Advantage family of products has what you need for a complete flea treatment and prevention plan, including monthly topical treatments, pet shampoos and sprays, household sprays for carpets and crevices, and even a yard and premise spray.

Shop Advantage

Frequently bought together

Questions & Answers

1 Customer Questions

How do you apply this product?

Answer by Chewy • Jun 23, 2025
Apply this easy-to-apply topical treatment to your dog once every 30 days according to the complete directions for use on the product label. It can be applied to two to three spots along the dog's back, from the shoulder to the base of the tail. The hair should be parted at each spot to expose the skin, and the solution should be squeezed directly onto the skin, not the fur.
Reviews
Write a Review
4.2
Rated 4.2 out of 5 stars
251 Ratings
Terms & Conditions

Customers Mention

Chewy identifies key considerations with the help of artificial intelligence and our veterinarians.

Ease of Use

77% Positive

Effectiveness

75% Positive

Ingredients

76% Positive

Long-Term Benefits

72% Positive

67 Customer Reviews

Always consult a veterinarian about your pet’s health needs. Customer reviews should not be used as medical advice.

Rated 5 out of 5 stars
By Aaron on Nov 6, 2025

K9 Advantec Flea and Tick

It works well. It’s not very expensive as the chews are. My littlest dog I saw itch a few times still but I don’t see any fleas. Someone put a don inside our back

It works well. It’s not very expensive as the chews are. My littlest dog I saw itch a few times still but I don’t see any fleas. Someone put a don inside our back yard that looked like one of our dogs but wasn’t. It was covered in fleas and had a broken leg. Poor thing. It brought a bunch of fleas that we normally do not have to worry about. This product along with flea baths has kept our 3 chi-weanies itch free. Definitely going to buy more. It’s a monthly solution that goes directly on their backs. And Chewy is a Great pet store. The convenience of ordering online makes my life so much better! I am so glad I found Chewys. I’ve used them for lots of stuff over the years. Never disappointed. One time I did have an order issue but they fixed it quickly and I wound up with more than I originally ordered for free. Totally happy with the products and the service!!!

Rated 2 out of 5 stars
By Hailey on Oct 26, 2025

Doesn’t Last a Full Month

Bought these for all 12 of my dogs and bought the cat version for my 6 cats. Despite saying they are monthly doses, they do not last the full month. You’d be lucky

Bought these for all 12 of my dogs and bought the cat version for my 6 cats. Despite saying they are monthly doses, they do not last the full month. You’d be lucky to get 2 weeks flea free while using these. Applied it exactly how it says on the back, the product just isn’t what it says it is. Do yourself and your pets a favor and buy a different topical preventative.

Rated 2 out of 5 stars
By Chelsea on Dec 3, 2025

Irritated dog’s skin

I gave this 2 stars because while it did keep away the fleas and ticks, my 3.5lb Chihuahua was so bothered by this, she kept hitting and itching. Take this with

I gave this 2 stars because while it did keep away the fleas and ticks, my 3.5lb Chihuahua was so bothered by this, she kept hitting and itching. Take this with a grain of salt as again she is a very small breed.

Rated 1 out of 5 stars
By Anna on Nov 18, 2025

Doesn’t work

Didn’t kill the fleas on either dog despite following directions carefully. Even treated the house and washed all the bedding despite the fact that it was a mild

Didn’t kill the fleas on either dog despite following directions carefully. Even treated the house and washed all the bedding despite the fact that it was a mild infestation. I don’t think there were even LESS fleas it seemed to have zero effect at all.

Rated 1 out of 5 stars
By Desiree on Oct 6, 2025

Terrible chemicals

Unfortunately, after using this product correctly, my elderly dog crossed over the rainbow bridge 6 days after application. She was a healthy old lady with life

Unfortunately, after using this product correctly, my elderly dog crossed over the rainbow bridge 6 days after application. She was a healthy old lady with life left in her until I used this product. She declined fast and hard and my heart broke watching her downfall. SOMETHING, some chemial Advantix is using is killing poor family members. My heart and my family’s hearts are broken.

Rated 2 out of 5 stars
By Naia on Jan 4, 2026

Doesn’t work

It doesn’t work anymore. I wish there was an effective flea medication on the market but they’ve adapted and are super resistant

It doesn’t work anymore. I wish there was an effective flea medication on the market but they’ve adapted and are super resistant

Rated 5 out of 5 stars
By Charlotte on Nov 11, 2025

it works

it is expensive, I have 4 dogs and 3 cats, however; that is my choice to do rescue, i just wish the drops were less expensive. I love the convenience that Chewy

it is expensive, I have 4 dogs and 3 cats, however; that is my choice to do rescue, i just wish the drops were less expensive. I love the convenience that Chewy offers.

Rated 1 out of 5 stars
By jerri on Aug 17, 2025

Sadly no longer works on fleas or ticks

Perhaps, the warming climate changes are causing fleas and ticks to evolve or at least get stronger with longer active seasons. My 6.5 pound Chihuahua has been

Perhaps, the warming climate changes are causing fleas and ticks to evolve or at least get stronger with longer active seasons. My 6.5 pound Chihuahua has been consumed with fleas and for the first time ever even by ticks this summer. Because we have been using K9 Advantix for years with success, its total failure this summer caught us by surprise. Our older little boy has suffered dearly. They were out of control before we even realized what hit us. Pest company has treated inside and out and we do not think we are alone this year from talking to others. Here’s hoping we find something new and still safe for us and our pup

Rated 2 out of 5 stars
By Raven on Dec 20, 2025

The delivery

They left my box next to my dumpster and I nearly threw it in the trash thinking it was an empty box

They left my box next to my dumpster and I nearly threw it in the trash thinking it was an empty box

Rated 3 out of 5 stars
By Sarajanne on Dec 6, 2025

Allergy

I was using this for a while but stopped using after my Peppa started scratching a day afterwards.

I was using this for a while but stopped using after my Peppa started scratching a day afterwards.