Trifexis Costco Review

Dogs are part of the family for many of us, therefore, we want to provide them with the best available all-round healthcare including the best dog flea and tick control, at Costco, Trifexis is one of the best medications to provide comprehensive protection for your dog in a number of key areas.


Trifexis is highly effective in combatting a variety of issues which your beloved pet may encounter.

These include heartworm, something which can have a serious and sometimes fatal impact on your dog’s health. Here we will outline how Trifexis can benefit your pet and how it should be used safely and to best effect.


trifexis costco review

Firstly, let’s take a more in-depth look at what Trifexis actually is and how it can benefit your dog.

It is important to note that Trifexis is a prescription only medication for dogs. This means it can only be obtained by visiting your veterinarian first and receiving a prescription.

Trifexis possesses the active ingredients Spinosad and Milbemycin oxime. It is used to prevent heartworm, a condition which can be very serious in your dog if untreated. It also treats hookworm, whipworm and roundworm in your dog.

These parasites can also be extremely harmful to the health of your dog. Finally, it helps to prevent flea and tick infestations. These are all ever-present threats which can have a great impact on both your pet and home.

Trifexis is fully approved by the FDA and the tablets come in chewable form, making them much easier for your dog to consume and relieving your stress at trying to coax your pet into taking them. They can be easily mixed in with some of your dog’s regular food and pass-by almost unnoticed.

They are suitable to be consumed by puppies of 8 weeks or older and the body weight of your dog should be at least 5lb before they consume Trifexis. There are a number of different varieties available depending upon the weight of your dog. Besides these effects, they can also work as an anti-inflammatory for your dog.

Trifexis is for the consumption of Dogs only and should be kept well out of the reach of children and other animals. 

  • Trifexis is fast acting and begins to work immediately, starting to kill off fleas noticeably within 30 minutes and before the can lay eggs.
  • It is very easy to administer in chewable form.
  • It helps to prevent a wide range of issues such as heart worm and other parasites.
  • The tasty flavors make it easily consumable by your dog.

As with any prescription medication, the drawback, although very rare, can be some adverse side-effects. Therefore it is important to closely monitor your pet for some time after consumption and use only as directed by your vet. This is especially true in cases where your dog may have some pre-existing condition or is a puppy aged under 14 weeks.

Directions for Use

Below we have listed the appropriate dosage of Trifexis, taking into consideration the weight of your dog. Again this should be taken only as a guideline and not used without prior consultation with you vet.

5-10 lbs: Give one tablet (Pink box)

10.1-20 lbs: Give one tablet (Orange box)

20.1-40 lbs: Give one tablet (Green box)

40.1-60 lbs: Give one tablet (Blue box)

60.1-120 lbs: Give one tablet (Brown box)

Over 120 lbs : Administer the appropriate combination of tablets

Trifexis should be administered only to your dog and in the prescribed oral form. In terms of storage, you should ensure that it is stored at room temperature and always check the expiry date before use.


The two major competitors to Trifexis in this market are Sentinel and Frontline Plus. Both of these brands have been in the market for a longer period of time and contain some but not all the benefits of Trifexis.

In the case of Frontline, it can be available without prescription but the method of application is different in that it is applied directly to the skin which can often be more cumbersome and it also tends to react slower, often showing signs of impact between 12 and 48 hours. Trifexis gets to work within 30minutes.

In terms of heartworm, Sentinel is the closest competitor to Trifexis. It performs the same functions on this parasite and is also consumed in a pill form. The major advantage Trifexis possesses though is its deadly effectiveness at killing fleas, an issue which Sentinel does not target.

Overall, Trifexis offers a new and exciting way to combat all of these issues in one fast and easy to consume product. 


What is the shelf-life of Trifexis?

The usual shelf life of Trifexis is around 12 months. Having said that, you should always double check the expiration date before you give any medication to your dog. Also, ensure that you have been storing Trifexis at room temperature. If you have any doubts, do no use.

How often should the medication be administered?

Trifexis should be administered once a month. Each box contains 6 tablets. This provides for a course of 6 months. After completion of the course, you should consult your veterinarian again for another prescription if required.

How do I know if my dog needs Trifexis?

Heartworm is a parasite which you should take continuous, pro-active steps to avoid for your dog. These pro-active actions include regular dosing of Trifexis or one of its competitors. In terms of other conditions it can relieve, of your dog is suffering from a flea infestation, noted by the visual presence of fleas or other signs, you should consult your vet to prescribe Trifexis. 

What is the most convenient way to administer the pill?

That is up to your personal choice. Many dog-owners however recommend to place the tablet amongst some tasty snack or food. This means your dog may not notice the pill at all or even if they do, will be encouraged to consume it anyway. Peanut butter is often a tasty temptation. Luckily, Trifexis also comes with a tasty beef flavoring.