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Product Info
How to Use
Customer Reviews
Product Info
What is Trifexis?

Trifexis is a chewable tablet that kills fleas and prevents infestations, protects against heartworms, and treats and controls adult hookworm, roundworm, and whipworm infections. Trifexis requires a prescription from your veterinarian.


Dogs (8 weeks of age and older and weighing at least 5 lbs)

  • Begins killing biting fleas within 30 minutes
  • Kills fleas before they can lay eggs
  • Prevents heartworm disease
  • Treats and controls roundworms, hookworms, and whipworms
  • Artificial beef flavor made from pork liver and hydrolyzed soy
  • Easy-to-administer chewable tablet
How it Works:

Spinosad, an active ingredient in Trifexis, starts to work within 30 minutes to kill fleas and has been proven to kill 100% of all biting fleas within 4 hours. Trifexis also kills flea eggs before they can mature, which helps to end the flea life cycle. Trifexis prevents heartworm disease by killing microfilariae and larvae from maturing into adult heartworms.


Serious adverse reactions have been reported following concomitant extra-label use of ivermectin with spinosad alone, one of the components of Trifexis chewable tablets. 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. Puppies less than 14 weeks of age may experience a higher rate of vomiting. Consult your veterinarian for pregnant or lactating dogs.

Brand Name:

Trifexis (Elanco Animal Health)

Generic Name:

Spinosad and Milbemycin oxime

What is the most important information I should know about Trifexis:

Trifexis is a prescription medication FDA approved for use in dogs 8 weeks of age or older and 5 lbs of body weight or more. Trifexis contains spinosad and milbemycin oxime and is indicated for the prevention of heartworm disease. Trifexis kills fleas and is indicated for the prevention and treatment of flea infestations, and the treatment and control of adult hookworm, adult roundworm, and adult whipworm infections. Trifexis is available in a pink box for dogs 5 to 10 lbs (140mg/2.3mg)), Orange box for dogs 10.1 to 20 lbs (270mg/4.5mg), Green box for dogs 20.1 to 40 lbs (560mg/9.3mg), Blue box for dogs 40.1 to 60 lbs (810mg/13.5mg), and Brown box for dogs 60.1 to 120 lbs (1620mg/27mg). For dogs over 120 lbs give the appropriate combination of tablets.

What is Trifexis:

Trifexis is a chewable, beef flavored tablet that is made out of pork liver and hydrolyzed soy and given to your dog once month to prevent heartworm, to prevent and treat flea infestations, and to treat and control adult hookworm, roundworm, and whipworm infections. Trifexis chewable tablets are for monthly use in dogs and puppies 8 weeks of age and older and 5 lbs of body weight or more.

What should I discuss with my veterinarian before giving Trifexis to my pet:

Tell your veterinarian if you are planning on breeding your pet. Tell your veterinarian if your dog has a history of seizures (epilepsy).

How should this medication be given:

Give Trifexis chewable tablets with food. Give Trifexis chewable tablets once a month. Trifexis chewable tablets may be chewed, offered in food, or administered like other tablet medications. If vomiting occurs within 1 hour of administration, redose the pet with another full dose. Store Trifexis at room temperature (68-77° F). Consult your veterinarian for pregnant or lactating dogs.

What happens if I miss a dose:

Give the missed dose with food as soon as you remember and resume a monthly dosing schedule.

What happens if I overdose the pet:

Overdose of this medication is unlikely. However, if an overdose is suspected, contact your veterinarian or veterinary emergency room. Symptoms of overdose that may occur include vomiting.

What should I avoid while giving Trifexis:

Your pet may maintain normal activities and interactions while being given Trifexis. The safe use of Trifexis chewable tablets in male dogs intended for breeding has not been established.

What are the possible side effects of Trifexis:

Side effects that may occur include vomiting. If vomiting occurs within one hour of administration, redose with another full dose. Other side effects may occur. Continue giving Trifexis chewable tablets and talk to your veterinarian if your pet experiences decreased appetite, lethargy or decreased activity, diarrhea, cough, increased thirst, vocalization, increased appetite, redness of the skin, hyperactivity and excessive salivation. Talk to your veterinarian about any side effect that seems unusual or especially bothersome to the pet.

What other drugs will affect Trifexis:

Talk to your veterinarian before giving any prescription or over the counter medications.

Where can I get more information:

Your pharmacist has additional information about Trifexis written for health professionals that you may read.

How to Use
  • Please view the chart below for the correct dosage of Trifexis for your dog.

Trifexis does not protect against ticks. To help control ticks, try the Preventic Tick Collar.

Dogs (Over 8 weeks of age)
5 - 10 lbs
Give one tablet (Pink label box)
10.1 - 20 lbs
Give one tablet (Orange label box)
20.1 - 40 lbs
Give one tablet (Green label box)
40.1 - 60 lbs
Give one tablet (Blue label box)
60.1 - 120 lbs
Give one tablet (Brown label box)
Over 120 lbs
Administer the appropriate combination of tablets
Do not use!
Do not use!

Should be stored at room temperature. Keep away from pets and children.

Trifexis for Dogs 5 to 10 lbs:
Active Ingredients per tablet
140 mg
Milbemycin oxime
2.3 mg
Trifexis for Dogs 10.1 to 20 lbs:
Active Ingredients per tablet
270 mg
Milbemycin oxime
4.5 mg
Trifexis for Dogs 20.1 to 40 lbs:
Active Ingredients per tablet
560 mg
Milbemycin oxime
9.3 mg
Trifexis for Dogs 40.1 to 60 lbs:
Active Ingredients per tablet
810 mg
Milbemycin oxime
13.5 mg
Trifexis for Dogs 60.1 to 120 lbs:
Active Ingredients per tablet
1620 mg
Milbemycin oxime
27 mg
Customer Reviews
Trifexis is rated 3.7556 out of 5 by 450.
Rated 4 out of 5 by from Awesome idea! I love that I only have to give my dogs one "pill" for fleas and heart worms! The only reason I didn't give this product 5 stars is because my dogs won't eat it. One of them literally gags when he sniffs it. I have a special dog, this isn't the only thing that makes him gag. The other two dogs took it pretty easily for about a year and then it became more difficult. Eventually they wouldn't take them either. So now I have moved to 2 different meds. I so wish they could/would make this one more palatable.
Date published: 2016-05-03
Rated 5 out of 5 by from Performs reliably and does not make the animal sic Performs reliably and does not make the animal sick.
Date published: 2016-05-02
Rated 4 out of 5 by from Seems to Work Well After reading the reviews of this product I was a little apprehensive about giving this to my 3 year old mix breed. The pill is a large chewable so it was had to get my dog to take it. She was a little more itchy than normal but did not have a bad reaction to the medication and still no signs of fleas.
Date published: 2016-04-26
Rated 5 out of 5 by from My first choice for my babies We have been buying Trifexis for our animals for 3.5 years now and every year our pets are relieved to take the medication! The fact that it protects against heartworms and intestinal worms is a bonus! I have noticed that with one or two of the 7 animals (2 cats and 5 dogs ranging from a 100 lb GS to a 2 lb Minni chiuahuah) sometimes we have a little trouble getting them to chew the tablets the flavor could be improved a little. Other than that I am happy to give this to my animals and have suffered no side effects.
Date published: 2016-04-13
Rated 5 out of 5 by from So far, so good!! I ordered 6 months of Triflexis online for my husky because my vet charges $28 dollars per pill! My husky weighs right under 60 pounds, and the vet prescribed him the 40-60 pound pill that's 810mg. Instead of ordering the 40-60 pound pills, I ordered 6 months of the 1620mg Triflexis pills instead. By chopping the pill equally in half, it's the same exact 40-60 pound 810mg dose. That gives me 12 months worth of Triflexis for $9.16 per pill compared to $28 dollars my vet charges!! Call me a cheapo all you want, but it would have cost me $336 dollars if I buy it from my vet for $28 dollars per pill for 12 months. Why not pay $110 dollars instead for the exact same thing? Prior to Triflexis, I was using K9-Advantage for my husky's flea protection. My area isn't infested with tick, and I used something else for tick when I take him camping with me. I thought K-9 Adv. protected my dog but within the first hour, I saw a few fleas crawl to the top of his coat. They were barely moving and in the process of dying. Then I used a flea comb 12 hours later, and I realized there were a lot more dead fleas then I expected. It's easier to give him 1 pill per month then 2. Also, at $9.16 per pill, you can't beat the price if you're using my method of ordering the 120 pound pills to cut in half while getting 12 months worth of supply too! Who wouldn't pay $110 dollars compared to $336 dollars for the same exact thing? It makes sense
Date published: 2016-04-13
Rated 5 out of 5 by from Love Trifexis I've been giving this to my Yorkshire Terrier for as long as she was old enough to take it = 2.5 years now- It's the Easiest way to know she's Protected from Fleas and Worms and Easy to Remember to give (once a month ) Pet Meds has the Best Price out there and was fast and easy to send the prescription in and get our "meds" delivered right to our door !
Date published: 2016-04-11
Rated 5 out of 5 by from Works Great!! I started my pugs and Boston on this med a month ago and everything seems to be working great. No side effects or problems.
Date published: 2016-04-03
Rated 5 out of 5 by from Flea away This is the 1st month all 3 of my babies have been on this and no fleas! No adverse reactions all is good!
Date published: 2016-03-30
  • 2016-05-05T06:00CST
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I still have some but they are over a year old can I still use them

Asked by: veeda
If your dog has not missed any monthly treatments, check the expiration date on your Trifexis to see if it is still good. Most product has an expiration date that is over a year from when our hospital purchases it from the manufacturer.
Answered by: SuztCVT
Date published: 2016-04-27

I have a 16 week old lab puppy who weighs 30 lbs. what size Trifkexus should I buy as he will go past the 40 lb within two months?

Asked by: Annie
Please check with your Pet's Veterinarian as to what the proper medication and dosage should be based on your pets age and size.
Answered by: Pharmacy Manager
Date published: 2016-04-25

How soon can I give my yorkie trifexis? 

Asked by: Rosie
Trifexis is safe to administer in pets 8 weeks or older who weigh at least 5 pounds.
Answered by: Lisa M
Date published: 2016-04-25

does this product also protect against ticks?

Asked by: Sydd
Trifexis does not provide protection against ticks.
Answered by: Lisa M
Date published: 2016-04-30

I have had my local Vet prescribe Trifexis and now he wants $140 refill. Can I scan my last scrip and send it to you for filling?

Asked by: John
We will contact your pet's clinic for the approval once you order Trifexis. We can only accept original prescription by mail or the vet may scan or email us the approval. We contact the vet for you once you place the order and most veterinarians respond within 24 hours and your pets prescription will ship out.
Answered by: Laura PetMed Pro
Date published: 2016-04-25

Will my dog need to be tested for heartworms yearly while on trifexis?

Asked by: Sharone
Since Trifexis is a prescription medication, your vet will need to perform a yearly exam and any required tests, including a heartworm test, depending upon your state's requirements. In Florida, an annual heartworm test is required.
Answered by: SuzyCVT
Date published: 2016-04-25

is it ok to cut the trifexis pill in half or to quarter it but give

but give the full pill cut in half or quartered?
Asked by: Carm
Some dogs tolerate the medication a little better if given it halved or quartered so long as the entire pill is given within an hour or two. Letting the pill "air out" for a couple of hours has been known to improve the palatability of the tablet for those very picky dogs.
Answered by: SuzyCVT
Date published: 2016-04-25

How many pills total will I be receiving?

Is it 6 packs of 6 pills or 6 pills total?
Asked by: Anonymous
A 6-pack always means one package of 6 tablets.
Answered by: SuzyCVT
Date published: 2016-04-30
  • 2016-05-05T06:11CST
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