This all-in-one tablet can help make it easier to keep pesky parasites away this spring (and all year long).
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Most of us dog parents use some form of heartworm prevention for our dogs. We may also give additional medications to keep fleas, ticks, and common intestinal parasites away. When it came time to pick the right product for my own dog, I opted for Simparica Trio. She was riddled with parasites when she was found as a stray, and then treated for heartworm disease just before I adopted her. Naturally, I want to make sure that she never has to go through that again. For me, Simparica Trio has made parasite control effective and easy—I just give her one chewable tablet each month.

If you're not already protecting your dog from common disease-causing parasites, then it's time to schedule a visit to your veterinarian. The American Heartworm Society recommends year-round heartworm prevention for all dogs in the United States, and the Companion Animal Parasite Council recommends broad-spectrum parasite control to prevent heartworms, intestinal parasites, fleas, and ticks for all dogs in North America.

Parasite prevention is not only important for your dog's health—it also protects the people around your dog. Humans can get infected with certain intestinal parasites, and fleas sometimes bite people. Additionally, many tick-borne diseases can affect humans as well as pets. Simparica Trio covers the most common dog parasites and typically costs less than buying separate products.

What Is Simparica Trio for Dogs?

Simparica Trio is the brand name of a chewable tablet that protects dogs from heartworm disease, fleas, five species of ticks, and two types of intestinal parasites. Manufactured by Zoetis, Simparica Trio contains three drugs: sarolaner, moxidectin, and pyrantel pamoate. It's only available with a prescription from your veterinarian, so you cannot get it over-the-counter.

Sarolaner is an acaricide (kills ticks and mites) and insecticide (kills fleas) belonging to the isoxazoline class of drugs. It works by creating uncontrolled neuromuscular activity leading to death in fleas as well as some ticks and mites. Sarolaner is effective against the following tick species:

Moxidectin is an antiparasitic drug in the macrocyclic lactone class. It kills heartworm larvae by causing paralysis that leads to the death of the parasite.

Pyrantel pamoate is a nematocide (kills some worms) belonging to the tetrahydropyrimidine class. It causes paralysis that leads to death of hookworms and roundworms.

Simparica Trio is just one of many parasite prevention products on the market for dogs. It's unique because it kills more types of parasites than any other combination product available to date. However, some dog parents prefer to use separate products. One common alternative is to give Heartgard for heartworms and intestinal parasites along with Bravecto to prevent fleas and ticks, but there are other choices out there. Your veterinarian is the best source of information and will help you choose the right product for your dog and your budget.

What Are Potential Simparica Trio Side Effects in Dogs?

Side effects are uncommon, but may occur in some cases. In clinical trials, vomiting and diarrhea were the most frequently reported adverse reactions. My personal dog has had no issues at all, and she's been on it for nearly two years. Other signs may include:

Contact your veterinarian if you notice these or other signs of illness after giving Simparica Trio to your dog.

Is Simparica Trio Safe for All Dogs?

Simparica Trio is considered safe for dogs as young as eight weeks old who weigh at least 2.8 pounds. However, the product has not been evaluated in breeding, pregnant, or lactating dogs.

It's important for your dog to be tested for heartworm disease before starting Simparica Trio (or any other heartworm prevention) because it will not kill adult heartworms and can actually worsen your dog's condition. Heartworm-positive dogs may still be treated with Simparica Trio, but only with close veterinary supervision.

Simparica Trio should be used with caution in dogs with a history of seizures. This is because drugs in the isoxazoline class have been associated with neurologic reactions including seizures, tremors, and ataxia in dogs with or without a history of neurologic disorders.

Simparica Trio Dosage

Simparica Trio should be given orally once a month at the recommended minimum doses: 0.54 milligrams of sarolaner, 0.011 mlilligrams of moxidectin, and 2.27 milligrams of pyrantel per pound of body weight. To make dosing easy, it's available for dogs in six sizes based on body weight range:

  • Gold: 2.8–5.5 pounds
  • Purple: 5.6–11 pounds
  • Caramel: 11.1–22 pounds
  • Blue: 22.1–44 pounds
  • Green: 44.1–88 pounds
  • Brown: 88.1–132 pounds

Simparica Trio can be given to dogs with or without food. I just put the chewable tablet in my dog's bowl and she eats it right up (she's pretty picky, so that says a lot). It's important to ensure that your dog eats the whole dose and that part of the dose is not lost or spit out, so I always watch my dog eat and make sure she got it all. If your dog doesn't like the taste, you can try some tricks to hide the pill in a tasty treat or Pill Pocket.

If you miss a dose of Simparica Trio, give it immediately and resume monthly dosing. Contact your vet if your dog misses a month or more of heartworm prevention—your dog might have become infected with heartworm larvae. A heartworm test may be necessary in about six months (that's how long it takes heartworm larvae to mature enough to show up on a test).

How Much Does Simparica Trio Cost?

The cost of Simparica Trio generally ranges from $22–30 per dose depending on the tablet size, number of doses, and source of purchase. It comes in a pack of six or 12, but veterinarians typically sell individual doses for growing puppies. The product can be purchased directly from your vet, from your vet's online pharmacy, or through an external online pharmacy with a valid prescription.

Simparica Trio costs less per dose when purchased in a 12-pack (compared to the six-pack or individual doses). Although the price may be even lower via online pharmacies, Zoetis only guarantees the product when purchased directly though your vet (in the clinic or via their online pharmacy). The company will not cover any products purchased through sites like Chewy or 1-800-Pet-Meds because they cannot be tracked to ensure they're legitimate and properly stored/handled (and due to the company's stance on product diversion).

Simparica Trio comes with a customer satisfaction guarantee: Zoetis will cover some or all vet expenses should your dog develop heartworm disease, Lyme disease, a flea infestation, hookworms, or roundworms. However, your dog must have a history of negative test results for these diseases. This is just another reason to follow your vet's recommendations for annual physical exams and tests.

Simparica Trio Drug Interactions and Warnings

Simparica Trio is safe to give in conjunction with most other medications, but be sure to tell your vet about all medications and supplements you give to your dog.