Which Heartworm Medicine Should You Pick

Which Heartworm Medicine Should You Pick

Author WDF Staff


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When getting a dog, most of us rarely thought about parasitic worms like heartworms. We focused on joy, happiness, and all the activities with our new furry family members. However, the reality of owning a dog means you have to take care of their health, and one of the most important things to do is keeping your dog parasite-free. We will focus on one particular worm that can cause all sorts of problems, the heartworm, and which heartworm medicine can help you deal with them.

What is a heartworm?

A heartworm is a parasite that lives in the dog’s heart, lungs, and arteries surrounding these organs. This nasty parasite feeds on the soft tissue, and if they are left unchecked, it will multiply and cause heartworm disease. It resembles a very thin spaghetti and can reach up to one foot in length.

How can my dog get infected?

Heartworms have a particularly nasty way of infecting your dog. They “travel through” mosquitoes. If a mosquito bites a dog infected with heartworm, tiny heartworm larvae will enter the mosquito’s body. When the mosquito bites another dog, the larvae can be transmitted to a healthy dog. There, the heartworm will develop and potentially cause heartworm disease.

If you want to know more about heartworms in dogs, check out this article - Heartworm in dogs.

Preventing heartworms

The best way to ensure your dog stays heartworm-free is by prevention. Many parasitic medicines can help you do that, and we bring you some of the best options available on the market today. If your dog takes heartworm preventatives regularly, the worm will get killed as soon as it enters your dog’s body. They will not even get the chance to develop and hurt your dog.

Here are the 5 best heartworm medicine for treatment and prevention of heartworm disease in dogs;

Heartgard Plus

We placed Heartgard Plus as the top pick on this list because of the reviews and personal experience with this medicine. We don’t live in an area where heartworm infestations are common, but unfortunately, after one summer, our dog got infected. The good news was our vet advised us to get our dog on this medication, and the results were phenomenal. Heartgard will clear 100% of adult worms, and our dog didn’t have any side effects even though they are possible. You can read more about it here - Heartgard for dogs. You will need a valid prescription, and if you have it, you can order it from Chewy’s online pharmacy.

Interceptor Plus

Our second pick is Interceptor Plus. Not only will it eliminate heartworm, but it will also eliminate other common worms that can infect your dog. This medication is effective against tapeworms, roundworms, hookworms, and whipworms. It offers complete protection and treatment. That makes it one of the best choices dog owners can make for their dog’s health. It comes in the form of a chewable tablet, so most dogs have no issues taking it. This is another prescription medication.


Many dog owners reported terrific results with Trifexis heartworm medication. This is an excellent product for treating and preventing heartworm infestations. It comes in different sizes, so the only thing you have to do is to make sure you ordered the correct size. This medication combines spinosad and milbemycin oxime to free your dog of fleas, roundworms, hookworms, and whipworms. Plus, it comes as a beef-flavored chewable tablet, so you can be sure your dog will absolutely love it.

Tri-Heart Plus

Tri-Heart Plus is Merck’s way of dealing with heartworms. Unlike our previous pick, this medication combines ivermectin and pyrantel to offer protection against heartworms, roundworms, and hookworms. These parasites can cause all sorts of health issues, so you should make sure your dog is protected. Luckily, Tri-Heart Plus is considered fairly safe and very effective. If you are traveling to warm areas where mosquitoes are, you should make sure your dog is protected. Like all other products on this list, you will need a valid vet prescription.


Sentinel is another great medication from Merck Animal Health. This medication will require a prescription and a current heartworm result. It is highly effective in dealing with heartworms, roundworms, hookworms, whipworms, and fleas. It is our advice you talk to other dog owners about these drugs and see their experience. We are sure that dog owners who used Sentinel for their dogs will have only positive things to say about it. In the end, the most important thing is that it keeps your dog parasite-free without causing them adverse reactions.

World Dog Finder team

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