TRIFEXIS Chewable Tablet for Dogs, 20.1-40 lbs, (Green Box), 6 Chewable Tablets (6-mos. supply) -

Trifexis Chewable Tablet for Dogs, 20.1-40 lbs, (Green Box)

By Trifexis
Rated 4.4471 out of 5 stars
Prescription Item
Pet Weight

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$129.19Chewy Price
$132.42Chewy Price
$122.73Autoship Price
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About This Item


Your furry friend must have a current heartworm test result on file with your veterinarian in order to be prescribed heartworm medication. Please visit your veterinarian to have this test performed annually to protect your four-legged friend. Trifexis (spinosad + milbemycin oxime) is the monthly, beef-flavored tablet prescribed to kill fleas and prevent flea infestations, prevent heartworm disease, and treat and control adult hookworm, roundworm and whipworm infections in dogs. With flea medicine, heartworm preventive and intestinal parasite control in one, get the peace of mind that comes from protecting your canine companion.

Proudly sourced directly from the manufacturer or their approved distributor. Guaranteed genuine and backed by the manufacturer.

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Play Video: Learn More About Trifexis From Our Team of Experts
Learn More About Trifexis From Our Team of Experts

About Trifexis

Dosed By Weight

Trifexis comes in five different strengths to provide custom-tailored dosing for a wide range of dogs. Just one tablet provides the correct amount your pup needs to protect him for a whole month from 5 different types of parasites. Trifexis works for dogs 8 weeks and older, with dosing for dogs from 5 pounds to 120 pounds—and beyond!

5 - 10 LBS
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10.1 - 20 LBS
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20.1 - 40 LBS
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40.1 - 60 LBS
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60.1 - 120 LBS
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Trifexis prevents heartworm disease. Trifexis kills fleas and prevents flea infestations, and treats and controls adult hookworm, roundworm and whipworm infections in dogs and puppies 8 weeks and older and 5 pounds or more.

Important Safety Information

The use of ivermectin at higher than FDA-approved doses at the same time as Trifexis can result in serious side effects. Treatment with fewer than three monthly doses after the last exposure to mosquitoes may not provide complete heartworm prevention. Prior to administration of Trifexis, dogs should be tested for existing heartworm infection. Use with caution in breeding females. The safe use of Trifexis in breeding males has not been evaluated. Use with caution in dogs with pre-existing epilepsy. The most common adverse reactions reported are vomiting, decreased activity, itching, decreased appetite, and diarrhea. To ensure heartworm prevention, observe your dog for one hour after administration. If vomiting occurs within an hour of administration, redose with another full dose. Puppies less than 14 weeks of age may experience a higher rate of vomiting. For complete safety information, please see Trifexis product label or ask your veterinarian.
Trifexis Product Label

About Trifexis

Trifexis is a once-a-month, beef-flavored tablet that provides broad protection against a range of parasites. It kills fleas, prevents flea infestations, prevents heartworm disease, and treats and controls adult hookworm, roundworm, and whipworm infections. Protect your dog with convenient parasite protection that lasts all month long.
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ReviewsWrite a Review

Rated 4.4471 out of 5 stars
208 Reviews
Would recommend to a friend

208 Customer Reviews

Rated 5 out of 5 stars
By Ojay on Dec 11, 2022

modern problems with modern solutions

This product is amazing! I highly recommend it because it works very well, but since it is a pill (which sucks but there is a way around it!), it was hard to give to my little dude until I thought to myself, why not crumble the pill and mash it up and give it to him?. That is exactly what I did, before taking the actual pill out of the silver packaging, I literally ever so slightly try to smash the pill in the packaging, once I think it is powdery, I then open the packaging from the little corner and voila! You have a powdery pill. What do you do from there on you may think? Either put the powdery pill in a treat (pill pocket, or some cheese) or put it into the food, one way or another your pup will consume the pill in a non pill form, this has been working pretty decently for me for a while! Hope this helps some folks who have been having trouble with this stuff! It costs a pretty penny but works amazingly!

Rated 5 out of 5 stars
By 1MichelinStar on Nov 4, 2022

Ground beef

"Trifexis works great, but our dogs hate it!" Is pretty much the theme in Trifexis reviews. I am here to offer a solution I discovered: Wrap Trifexis in raw ground beef and dogs will love medicine time. This is based on experience, check my resume below. Every month for years, I hated when my calendar alerted me to give our dogs their Trifexis. I found myself staring in the fridge for a tasty left over, a fine aged cheese, crappy cheese, cheese-food-product, hot dogs, sausage, bacon, dog treats and fish sauce, ground it into dust using a mortar and pestle and mixed with peanut butter... literally nothing could mask their Trifexis. Ultimately, after the air would fill with words I can't have our son repeat and yelling about why such an expensive dog pill was clearly not made by dog people for dogs my wife would offer up her services. Her finger would take the now gooey pill stuck to her finger like a booger and cram it down their throats. Not cool and the dogs weren't having fun either. The vet had no suggestions beyond what had already been tried. One day the calendar notification dinged on my phone and the dreaded word "Trifexis" appeared. I grabbed the dogs boxes of Trifexis cut the pills in quarters as usual (knowing that they really detect the whole pill) and opened the fridge in search of a masking agent. Then, something unusual happened, as if the heavens opened up, a beam of fridge light shined down from above onto some ground beef waiting for me to transform it into chili and beans that night. I grabbed a chunk of it and made Trifexis stuffed meatballs out of each piece of pill! The dogs gobbled up their medicine and wanted more! I received my first Michelin Star and now, finally, I live a more stress-free life. My potty mouth has turned into laughter and praise. The dogs running and hiding behind the sofa has turned into salivating and tail wagging. And we all live happily ever after. We love Trifexis calendar notifications now!

Rated 5 out of 5 stars
By Doggos on Oct 28, 2022

Very Happy

I am very happy with the smooth transaction between Chewy and my vet. I prefer this product to the ones my vet Keeps in stock.

Rated 4 out of 5 stars
By Pattie on Jul 2, 2022

Great product, but doesn't work if you can't get them to eat it

I think Trifexis works really well, and I was very happy to be giving my dog an organic product like spinosad. However.... my dog HATES the pills. They seem to be the only thing on the planet this dog will not happily wolf down. No tricks worked--he left it in his food bowl, ate the treat around it and spit out the pill, etc. I tried crushing but it's pretty hard to crush. Even shoving it all the way to the back of his throat didn't work. I ended up having to DISSOLVE it in some green bean juice and pour it on his food. I wouldn't mind that, but I can't find any info anywhere about whether dissolving it decreases its effectiveness. So... we used up his prescription and switched to another brand. I'd still prefer to use Trifexis if I could.

Rated 1 out of 5 stars
By Blue on Aug 1, 2022

Would not eat it

My dog would not eat this pill no matter if I used peanut butter, cheese whiz, wrapped inside meat, pill pockets and mixed with wet food. I would force the pill down his throat. He didn't like that and neither did I. So I was forced to change to Heartgard and NexGard. It might be a good item but if your dog won't take it, then its a waste of money.

Rated 5 out of 5 stars
By Missy on Dec 14, 2022

Nice Product

Easy to give your dog and seems to work great. Easy to order also.

Rated 5 out of 5 stars
By Sammie4Chewy on Jul 14, 2022

Trifexis Tablets

I am so happy this is working for our 6 month old beagle. This does it all! I really don’t like the oil based coverage and have heard some negative comments on the seresto for very young small dogs. Have used them for years on my big dogs, no problem.

Rated 4 out of 5 stars
By SixPup on May 23, 2022

Trusted and used for years

My 40lb mutt has had great results, and I can't complain on its intent. I agree with some others on smell, as it is a chalky type aromatic when you crunch it up. Speaking of crunching, my dog will not eat this standalone. I use a small bit of wet food and no issue. Little pricey, but I'm content on execution, and delighted with results. Buying from Chewy will definitely save you money as well compared to vet costs.

Rated 5 out of 5 stars
By Sammy on Oct 6, 2022

Everything went great

Everything went great and right on time!! Everyone was cooperative and nice

Rated 2 out of 5 stars
By MKL77 on Jun 23, 2022

It's a no from me.

I had the hardest time getting my dogs to swallow these pills. They hated them! The pills worked okay, but I would never buy again because they were not worth the headache.