About Trifexis

Trifexis for dogs: 3-in-1 parasite protection

With Trifexis® (spinosad + milbemycin oxime), protecting your dog from parasites is one and done: once a month, every month. Trifexis is the monthly, beef-flavored tablet for dogs that:

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Kills fleas in dogs and prevents infestations

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Prevents heartworm disease in dogs

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Treats and controls adult hookworm*, roundworm and whipworm infections
*A. caninum

Give parasites in dogs a one-two punch

Parasites can be practically anywhere your dog goes—including your home and yard—and they pose a serious threat to your dog’s health. That’s why you need to make sure your dog is protected.

Trifexis combines two powerful active ingredients that protect your dog safely and effectively against three types of dangerous parasites. Plus, you give it orally, so there's no need to isolate your dog from your kids or other pets, which means more play time and less waiting around. But remember, Trifexis is only for dogs and puppies 8 weeks and older and 5 pounds and greater.


Talk to your veterinarian

Your veterinarian is your best source of advice about your dog's health care. It‘s why you should see your veterinarian to get the proven parasite protection of Trifexis.


#1 prescribed combo parasite protection for dogs

Trifexis is a prescription product that should only be purchased from a veterinarian.
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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, depression/lethargy, 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. Like all medications, keep Trifexis out of reach of children.

View full product label for complete safety information.