Is Trifexis on Sale? November 2026

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  Buying guide · 10 picksBest flea treatments for dogs

Questions and answers

What does Trifexis protect against?

It kills fleas and prevents flea infestations, prevents heartworm disease, and treats and controls roundworms, hookworms and tapeworms. It does not repel ticks, so dogs in tick country usually need a separate tick product.

How is Trifexis given?

It is a beef-flavored chewable given once a month with food for better absorption. Dogs should be at least 8 weeks old and weigh at least 5 pounds, and a negative heartworm test is needed before starting.

Does Trifexis require a prescription?

Yes. It is prescription-only in the US, so a veterinarian must authorize the order. Stores typically ask for your vet's details during checkout and confirm the prescription before shipping.

What are the common side effects?

Vomiting, diarrhea, lethargy and decreased appetite are the most reported reactions, usually mild and short-lived. Giving the chew with a meal reduces stomach upset, and reactions should be reported to your vet.

Is Trifexis safe for breeding or pregnant dogs?

Safety in breeding, pregnant or lactating dogs has not been established, so use in those animals is only on a vet's direction. Collies and other herding breeds should also be cleared by a vet because of milbemycin sensitivity.

Are there Trifexis discount codes?

Deal.ai checks what Trifexis products actually cost at every store, so a real markdown shows on this page as a deal as soon as it starts, and each product's page has its price history to tell a sale from its usual price.