PetArmor® CAPACTION® (nitenpyram) Oral Flea Treatment for Dogs - 6 / 2-25lbs

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4.2 from 33,397 reviews

365K+ sold

PetArmor CAPACTION (nitenpyram) Oral Flea Treatment for Dogs — 2–25 lbs, 6 Tablets

Name: PetArmor® CAPACTION® (nitenpyram) Oral Flea Treatment for Dogs - 6 / 2-25lbs
Brand: PetArmor
SKU: Y2R865B56
Price: 31.49 USD
Availability: InStock
Rating: 4.18 (33397 reviews)

When fleas show up on your dog, this oral tablet gets to work fast — it starts killing adult fleas within 30 minutes. Available without a prescription and offered in weight-based options, CAPACTION is a simple first step for new flea-treatment buyers.

$31.49

Key Features

•

Starts killing adult fleas within 30 minutes of a single oral dose

•

Sized for smaller dogs weighing 2 to 25 lbs

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Contains nitenpyram, the same active ingredient found in CAPSTAR

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Give as often as once a day if fleas return; safe for pregnant or breeding dogs, as directed

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Easy oral tablet — no messy topical to rub in, and no prescription needed

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Includes 6 doses to kill adult fleas that can trigger flea allergy dermatitis

Count

Weight

> 25lbs

2-25lbs

Free shipping on orders over $25

Delivers in 2-3 days

30-day free returns

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Customer confidence

365K+ recently bought this product

Top seller

99% of customers keep this item

Low return rate

Over 365K+ happy customers

It DOES work!

Worth every penny. My dog has been infested with fleas. Tried everything, including yard treatments. Buy it! Worth it.

Abby

A Must Have Flea Product

I keep PetArmor CAPACTION oral flea treatment tablets on hand to administer in that situation. None of my dogs have experienced side effects. I highly recommend this product.

Mary Rae Fouts

Dogs love it!

I use this product often because I have 6 dogs. Perfect if a dog has a lot of fleas. Good price, quick delivery and comes with qty 6, so 1 for each of my dogs.

Andrew

An owner checks a black Labrador's coat in a rain-damp mudroom.

Fast-acting relief

Fleas gone fast, without the guesswork

Fleas can turn up quickly. CAPACTION is an oral tablet that starts killing adult fleas within 30 minutes, so relief begins the same day you notice a problem — no waiting and no mess to rub in.

How it works

One oral tablet that targets adult fleas

CAPACTION contains nitenpyram, the same active ingredient as CAPSTAR. You give it by mouth, and it goes to work on the adult fleas already on your dog. It can be given as often as once a day if fleas come back — always use as directed.

A large brown dog sits by its water bowl beside a PetArmor CAPACTION six-tablet box labeled for dogs over 25 lb.

A woman with a tote bag stands beside a small brown-and-white dog in a pet store aisle, looking at shelves of bottles and packaged products.

New to flea treatment?

A simple first choice you can trust

If this is your first flea treatment, we kept it straightforward. Choose the option that matches your dog's weight, give one tablet, and know what to expect. Available without a prescription, CAPACTION is an easy way to tackle an active adult-flea problem.

84%

Would recommend to a friend or family member¹

5 Million

Trusted by over 5 million pets annually²

Source: (1) Stackline, (2) Numerator Panel, data on file

How We Stack Up

CAPACTION oral tablets

Topical spot-on treatments

Flea collars

Start killing the adult fleas on your dog the same day

Give it by mouth — nothing to rub onto skin or fur

Match the dose to your dog's weight range

Buy it without a prescription

Re-dose as often as once a day if fleas return

Simple and mess-free for an active flea problem

Hands check a large shepherd mix's coat on a covered porch after rain.

Relief that starts fast

Spot fleas today, act today. CAPACTION starts killing adult fleas within 30 minutes of a single oral dose, so your dog gets relief the same day.

A beagle waits for a treat as a sealed flea-treatment box rests at the room's edge.

Easy to give, easy to trust

It's an oral tablet — no messy topical to rub in or dry. Use as directed, and give as often as once a day if fleas come back.

A large Labrador stands by its owner as a sealed flea-treatment box rests beside a harness.

An option sized for your dog

Choose by weight — options for dogs 2 to 25 lbs and for dogs over 25 lbs, in 6- or 12-tablet packs — so you can pick what fits your dog and your needs.

Frequently Asked Questions

PetArmor® CAPACTION® is an oral flea treatment for dogs. Its active ingredient is nitenpyram, and it kills adult fleas. Choose the dog option that matches your pet's weight and follow the package directions.

A small terrier and its owner pause beside a fern-lined trail after rain.

4.2 Star Rating

Discover why customers choose us

We've collected over 33,397 reviews from shoppers on our website and major retailers.

All

Effectiveness

Price

Fast acting

Quality

Alyssa aguilar

May 18, 2025

Highly recommend for a temporary solution!!

Package came a little bent but I assume that’s because of how flat the box is. Medication kicked in about 30-40 minutes and I immediately started seeing the fleas come off. Not specifically sure how the medication works but to me it very much made the fleas “drunk” to where they would fall off and eventually die.Like I said, temporary fix till I can get my dog to the vet to get him Trifexis. Really enjoyed the popping the drink fleas!

Yuri

Jun 10, 2024

It works

Having just received medication today, I gave it to her around 6pm, and within 30 minutes she started acting crazy. There were fleas running all over her body waiting to come out. She was itching like crazy. As she scratched, dead and alive fleas jumped out. I also helped her get some off with a comb. I got a plastic cup with water and threw about two cups full of fleas into it. As an indoor dog, she only goes out for the restroom occasionally, but she does escape, and that's how she gets fleas, especially from stray cats roaming around our neighborhood. It is hoped that fleas will disappear soon. It must be given to her by a Winnie, the taste she hates. I really hope this helps my poor baby, she's been scratching for days, she's going bald.

Patricia S.

Apr 28, 2026

Works better than capstar.

I gave my Blue heeler one of these capsules in the next day every flea was gone. She stays in a half acre pen with a dog house inside the barn and we put cedar shavings down along with diametric Earth. We also put the diatometric Earth on the dog. You can purchase that from Tractor supply company. They can even eat it. It keeps ticks flies and bugs away and it's great for gardeners and yards.

Mary Rae Fouts

Sep 9, 2025

A Must Have Flea Product For Fleas Between Regular Monthly Flea Medication Doses!

Fleas are bad all year round here in the San Francisco Bay Area. We have always used a monthly dose of flea preventative on all of our dogs. In spite of that, we occasionally see live fleas between doses.I keep PetArmor CAPACTION oral flea treatment tablets on hand to administer in that situation. Tablets are easy to wrap in some creamy peanut butter and give to the dog. The flea treatment starts killing fleas within 30 minutes, and continues for about 24 yours. It is easy to see the treatment is working, as my dogs are always quickly more comfortable.Note: Flea eggs on your dog are not killed by this treatment, only live fleas. I would not recommend this as your only flea preventative for your dog, but rather an extra treatment when needed.None of my dogs have experienced side effects. I highly recommend this product.

Andrea

Sep 1, 2025

Dogs love it! Starts working in 30 minutes

I use this product often because I have 6 dogs. It works great to get rid of adult fleas. Starts working within 30 minutes and lasts up to 24 hours. Perfect if a dog has alot of fleas. After one pill I wait a day and apply monthly products. Good price, quick delivery and comes with qty 6, so 1 for each of my dogs.

Jamie Vaughn

Jul 4, 2025

NO MORE SCRATCHING!

We’ve been battling fleas with our two small dogs for what feels like forever. Our older dog has extreme skin irritation because of it and our younger dog was constantly scratching!! We’ve tried multiple flea medications and they just weren’t working like we wanted them to. I ordered this item and gave our pups one tablet each last night. And let me tell you - THEY HAVE NOT SCRATCHED SINCE! It does take about 30 minutes for the tablet to kick in, but when it does, it’s a game changer! I definitely recommend this product. 10/10! For sure! If I ever need to purchase flea/tick medication again, this will be the one!

Blake Rice

Jun 26, 2025

Fantastic temporary solution! Solves the issue quickly.

Why did you pick this product vs others?:I’ve seen a huge difference in the amount that my pup has been itching/biting himself. It’s a great quick acting temporary solution. I normally do the topical treatment from this company and I unfortunately forgot for a month. Hoping this will get rid of the issue until the topical can be reapplied!Tick resistance:Seems to be working already! Noticed a big difference in 24 hours.Safety:Pills are in sealed packaging (individually).Smell:Odorless

Abby

Jan 19, 2025

It DOES work!

Worth every penny. Literally see fleas falling off my dog in less than a hour. My dog has been invested with fleas. Tired everything, including yard treatments. But since we live in a rental and in order for the fleas to be done we’d have to get rid of trees and what not. I give one to my dog every other night when I bro get in, every morning I wake up to sweep up dead fleas, gross but honestly satisfying how fast it works. Buy it! Worth it.

Amazon Customer

Aug 26, 2024

Works FAST

My dog is regularly flea treated, but for some reason this year we’ve had issues with fleas outdoors. Every time we took her outside she would come in itching uncontrollably.This was a lifesaver for my dog! These tablets started working within 30 minutes, quickly relieving my poor dog’s itching from fleas. I love that it can be used in combination with regular topical treatment and will keep my home free of a flea infestation.

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