Using Trifexis

How should I give Trifexis® (SPINOSAD + MILBEMYCIN OXIME) to my dog?

How to give your dog Trifexis

View video transcript

[Dr. Jeff Werber:
Trifexis delivers three types of parasite protection in a flavored tablet given once a month. You can give it to your dog directly out of your hand or place it in her food bowl. Other dogs prefer that the tablet be placed inside of a treat.

How ever you choose to administer Trifexis, it’s important to ensure your dog ingests the entire tablet so she receives a full dose. Observe your dog for one hour after you give her Trifexis. If your dog vomits within an hour, give her another full dose. Administer Trifexis with a meal for maximum effectiveness.

It’s also important to administer Trifexis every month as directed by your veterinarian. This will help ensure that your dog receives continuous protection against fleas, heartworm disease and intestinal parasites. To help keep your dog on schedule with each treatment, sign up to receive monthly reminder emails or text messages at

Ask about Trifexis, the combination product that kills fleas and prevents infestations, prevents heartworm disease, and treats and controls hookworm, roundworm and whipworm infections. See the full product label for complete safety information.

Serious adverse reactions have been reported following concomitant extra-label use of ivermectin with spinosad, one of the components of Trifexis. 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 dogs with pre-existing epilepsy.

The most common adverse reactions reported are vomiting, depression, itching and decreased appetite. To ensure heartworm prevention, observe your dog for one hour after administration. If vomiting occurs within an hour of administration, redose.]

Give Trifexis with food for maximum effectiveness. Trifexis is a chewable tablet and may be given like a treat. Consult your veterinarian regarding the need for year-round administration of Trifexis. Use the included stick-on calendar labels to remember your dog's monthly dosing schedule.

Learn more about Dosing

Do I have to give Trifexis with food?

Administer Trifexis with food for maximum effectiveness.

Can Trifexis tablets be crushed and put in food?

We did not conduct any studies where a crushed Trifexis tablet was added to food and fed to a dog. Given our knowledge of spinosad and milbemycin oxime, it should be stable if the tablet is crushed and consumed right away. The stability in food for any significant period of time, however, cannot be guaranteed. It is best to make sure your dog eats the meal immediately.

The package reads “chewable.” What if my dog swallows the tablet whole?

Given our knowledge of spinosad and milbemycin oxime, Trifexis will be effective if the tablet is consumed whole (not chewed).

View the dog owner information sheet for Trifexis

What if I give more than the prescribed amount of Trifexis to my dog?

Contact your veterinarian as soon as possible if you believe your dog has ingested more than the recommended dose of Trifexis. In a study in which dogs were dosed at one, three and five times the upper half of the recommended dose, dogs exhibited vomiting, tremors, decreased activity, salivation, coughing and vocalization.

Should I restrict either my dog’s activity or contact with my dog after the tablet is consumed?

You may maintain normal activities and interactions with your dog.

Does seeing fleas on my dog mean that the treatment is not working?

Trifexis kills fleas on dogs before they can lay eggs when used monthly and according to the label directions. Remember that all animals in the household should be treated with an approved flea product to help control the flea population. Your dog can continue to be exposed to fleas that live in the environment. When fleas jump onto and bite your dog, they will be killed by Trifexis. If, within a month after your dog receives Trifexis, you see fleas on your dog, they are most likely new fleas. These new fleas will be killed before they can produce eggs that contaminate the environment. Continued monthly use of Trifexis can protect against any new infestations.

Learn more about fleas

What if I see worms in my dog’s stool during the month after administration of Trifexis?

Trifexis is indicated to treat and control intestinal parasite infections of adult hookworms*, roundworms and whipworms in dogs. In occasional cases, it is possible that Trifexis’ action of killing intestinal worms will lead to your dog expelling them in stool. If you have questions, consult your veterinarian for measures you can take to prevent a reinfection of intestinal parasites.

*A. caninum

Learn more about Intestinal parasites

Can Trifexis be given to cats?

No, Trifexis is not approved for use in cats. Trifexis was developed exclusively for administration to dogs. If you’re looking for Elanco products that are approved for use in cats, learn more on the Elanco brands page