Everything you need to know about Heartgard Plus

Everything You Need To Know about Heartgard Plus

Heartworms are dangerous parasites that grow in a dog’s heart, blood vessels, and lungs. They multiply in favorable conditions causing a blockage, which eventually leads to high blood pressure and heart failure. Moreover, heartworms are difficult to treat and take a toll on the health of your pooch. Hence, it is preferable to prevent infection

Heartgard Plus is one of the best preventives which is trusted by pet parents across the world.

What is Heartgard Plus?

Heartgard Plus is a chewable preventive that prevents heartworm from infecting your furry baby. It comes as a beef-flavored chew and can be easily given as a treat. This potent treatment keeps your furry baby protected from heartworms and other intestinal worms, including roundworms and hookworms.

How does it work?

Heartgard Plus contains Ivermectin and Pyrantel as active constituents. These compounds cause neurological damage to the parasites, which leads to paralysis and eventually kills them.


Heartgard Plus chewable, when given orally according to the recommended dosage, is effective for a month. It directly affects the larval stage of Dirofilaria immitis (heartworm) after infection and prevents the development of worms. As a result of this, your pet remains safe from the infection showing no symptoms.

So, this was an insight into what Heartgard Plus does and how it works to keep your pet protected. Now, let’s get into how to give the right dosage.

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The minimum recommended dosage of Ivermectin is 2.72 mcg/ lb and for Pyrantel, it is 2.27 mg/ lb. Heartgard Plus is available in 3 different strengths, based on the dog’s weight and the quantity of active ingredients is:
Up to 25 lbs. — 68 mcg ivermectin/57 mg pyrantel (Blue Colored)
26 to 50 lbs. — 136 mcg ivermectin/114 mg pyrantel (Green Colored)
51 to 100 lbs. — 272 mcg ivermectin/227 mg pyrantel (Brown Colored)
For dogs over 100 lbs, use an appropriate combination of doses should be given.
Administration of Heartgard Plus is easier as these chews are readily taken by dogs. They can be directly offered to your pet or can be mixed with their food. Ensure that the dog finishes the complete dose.


Heartgard Plus is considered to be extremely safe to use in dogs, but certain precautions are important to know as a pet parent.

  • This treatment is safe to use in puppies from 6 weeks of age
  • Always get your pet tested for Heartworm before starting the treatment. Infected dogs must be treated for adult heartworms before commencing Heartgard Plus
  • In less common cases, some adverse reactions can cause vomiting, diarrhea, ataxia, staggering, lethargy, or convulsions.
  • Some breeds like Collies, German Shepherds, sheepdog breeds, terriers, silken Windhounds, and longhaired whippets have shown sensitivity to Ivermectin. So, it is suggested to consult a vet before administering Heartgard Plus.

Keeping your pooch healthy and happy is in your hands. Giving them effective treatment with precautions will prevent any discomfort and they will live happy life.


  1. Can heartworms be transmitted to unborn puppies?

Transmission of heartworm is only possible through a mosquito bite; this makes direct transmission from mother canine to unborn puppies impossible. However, they may get baby worms through the bloodstream and are at risk of getting infected, but these will be eliminated once you start with their preventive treatment.

  1. Heartgard v/s Heartgard Plus, what is the difference?

Heartgard protects only against heartworms, whereas Heartgard Plus prevents heartworms and treats intestinal worms like roundworms, hookworms, and other ascarids

  1. How quickly does Heartgard Plus work?

Heartgard Plus starts acting as soon as it is absorbed by your dog’s circulation system.

  1. Can Heartgard Plus be used in breeding, pregnant, or lactating dogs?

Yes, when used according to the recommended dosage, it is safe to use in all breeds of dogs including breeding, stud dogs, and pregnant and lactating females.

  1. What should I do if I miss a dose of Heartgard?

Although, your dog is still protected for up to 2 more weeks; however, the efficacy of the treatment will be reduced. This increases the chances of getting infected with heartworm.
Administer Heartgard Plus as soon as you recall and continue on the dosage schedule.

In case of more than two weeks since the missed dose, consult your veterinarian as the dog may need to go through the heartworm test before resuming the dosing schedule.