Using Tri-Heart Plus vs. Heartgard for Dogs Which Preventative Is Right for You and Your Dog?

Using Tri-Heart Plus vs. Heartgard for Dogs
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Let's face it, worms are icky whether they are outside or inside your pet. However, if these parasites get inside, they can cause great harm to both your pet's heart and gastrointestinal tract. Learn more here are about these two preventatives, Tri-Heart Plus and Heartgard for Dogs, so you can best protect your dog from intestinal parasites.

Most dog owners know that worms can be a serious threat to the health and well-being of our beloved pets. To get ahead of these nasty pests, dog owners should use a bit of preventative heartworm medicine for dogs. Below are descriptions and comparisons of two effective heartworm and internal parasite medicationsTri-Heart Plus vs. Heartgard.

What Types of Pests Do Tri-Heart Plus and Heartgard Kill?

Tri-Heart Plus and Heartgard are both oral medications that are effective at preventing heartworm infections in dogs. Heartworm pills for dogs like Heartgard protect against heartworms alone. Tri-Heart Plus, as its name implies, protects against three types of parasites: heartwormroundworm, and hookworm. 

Both of these medications are effective in heartworm prevention for dogs and should not be given to your pet if worms are already present.

Heartworm meds for dogs target internal parasites but do not guard against other pests like fleas or mites.

How Long Does a Dose Last?

Both Tri-Heart Plus and Heartgard are formulated to last for 30 days. They're both tasty flavored chewable tablets that your dogs should eat readily each month.

Should My Pet be Kept Inside or Alone After the Dose?

Tri-Heart Plus and Heartgard are oral medications, so you will not need to quarantine your dog or keep your dog inside after administration, as you might have to with spot-on parasite preventatives. The first thing you need to consider when setting up a quarantine is whether or not it's necessary. Sometimes "quarantine" can be used as a catch-all term for separation from other animals without considering if there's actually any risk of disease transmission. If your dog has been around other dogs but hasn't shown any signs of illness, there's probably no reason to place them in isolation.

The second thing you need to consider is why you're quarantining your dog in the first place. Is it because they've been exposed to an unknown pathogen? Are they showing symptoms of illness? Is there a potential health risk for others if they're not separated from their usual environment? These are all important factors that will help determine how long your dog should be kept away from other pets or people.

If you have multiple pets, give your quarantine dog separate dog bowls, keep them in separate dog cages, and also separate their dog chew toys. You wouldn't want the disease to spread (if your dog has it in the first place).

Are There Any Side Effects?

Both Tri-Heart and Heartgard contain ivermectin. Tri-Heart contains pyrantel as well. These drugs are toxic, and although their intended target is parasites, they can have an effect on your pet's well-being as well. 

Common side effects include  diarrheavomitinganorexiadepression or lethargy, mydriasis, ataxia, staggering, excess salivation, and convulsions. If any of these side effects present themselves while your dog is taking these medications, contact your veterinarian immediately.

Be sure your dog does not already have a full-stage worm infestation before beginning preventative treatment with these chewable medications. These drugs are for the prevention of parasites, not the treatment of an existing infestation.

Collies and other herding dogs are especially sensitive to ivermectin. You should discuss alternative options with your veterinarian.

There are a number of reasons why dog medications have side effects. First, the dosage is often adjusted based on the dog's weight and age, which means that there may be more or less of a certain ingredient in each pill. This means that one dog could react differently to an ingredient than another.

Secondly, the ingredients used in each medication vary from one manufacturer to another. A dog might react negatively to an ingredient in one brand but not another brand because the two manufacturers use different sources for their ingredients.

Thirdly, some dogs may simply be allergic to certain ingredients in their medications.

My Pet is Only a Few Weeks Old. Can I Use Tri-Heart Plus or Heartgard Safely?

Tri-Heart and Heartgard are both intended for use with puppies that are at least 6 weeks of age.

My Pet is Pregnant or Nursing. Can I Still Use One of These Medications?

Both Heartgard and Tri-Heart are safe for pregnant female dogs, as well as for both male and female dogs that are to be used for breeding. Both of these medications are available from your veterinarian by prescription only, so talk to them about using these drugs with your pregnant or breeding dogs. If you're still concerned, use the Seresto Flea Collar for Dogs to keep mosquitoes away. By keeping mosquitoes away, this dog collar will prevent your pregnant or nursing dog from getting heartworms and other diseases.

Pregnant dogs must be fed a balanced diet. This means that the amount of protein, fat, and carbohydrates in their food should be roughly equal. It's also important that pregnant dogs get all of their nutrients from food and not from supplements or vitamins. This will ensure that the puppies are getting everything they need to grow and develop properly.

If your dog is pregnant, it's important to keep an eye out for any changes in her behavior or personality. If she suddenly starts acting differently than she normally does, this could be a sign that something is wrong with her pregnancy, and you should take her to see your veterinarian right away.

How Do Tri-Heart Plus and Heartgard Work?

Ivermectin and pyrantel, the active ingredients in the Heartgard and Tri-Heart Plus medications, work in similar ways.

Ivermectin targets heartworms and causes paralysis in heartworms in the larval stage. Affected worms are unable to travel toward the dog’s heart, and so they die, unable to reach adulthood.

Pyrantel is a neuromuscular blocker. It, too, causes paralysis in roundworms and hookworms. When they become paralyzed, they lose their grip on the dog's intestines and are passed into the dog's stool.

Heartgard and Tri-Heart come in four dosage sizes that are administered to your dog based on their weight. It is crucial to administer the recommended dose to ensure efficacy and avoid any potential side effects.

Whether you choose Tri-Heart Plus or Heartgard for your dog, both medications are effective in heartworm prevention and controlling other internal parasites. Always consult your veterinarian for information summary and to ensure your dog is in good health before starting any heartworm preventative treatment.

These chewables provide an excellent form of heartworm control and ensure your dog’s freedom from these dangerous infections. Trust in the efficacy of these products, backed by veterinarians and the American Heartworm Society, to keep your pet safe and satisfied.



Pests controlled

 Recommended age of application


 Oral; 1-month dose by chewable tablet

 Larval heartworms

 6 weeks and older

 Tri-Heart Plus

 Oral; 1-month dose by chewable tablet

 Larval heartworms, intestinal round, and hookworms

 6 weeks and older

Frequently Asked Questions

Is Tri-Heart Plus the same as Heartgard Plus?

Yes, Tri-Heart Plus and Heartgard Plus are the same product. Tri-Heart Plus is a brand name for a medication that is used to prevent heartworm disease in dogs. Heartgard Plus is the same medication, but it is manufactured by a different company. Both Tri-Heart Plus and Heartgard Plus contain the active ingredient ivermectin, which is a medication that is effective at killing heartworm larvae and preventing them from developing into adult worms. Both medications are given orally to dogs on a monthly basis to prevent heartworm disease. It is important to follow the dosing instructions provided by your veterinarian and to give the medication to your dog consistently in order to provide maximum protection against heartworm disease.

What's the difference between Heartgard and Heartgard Plus?

Heartgard and Heartgard Plus are both medications used to prevent heartworm disease in dogs. Heartgard is a monthly chewable tablet that contains ivermectin, an antiparasitic drug that is effective against heartworms and other parasites. Heartgard Plus also contains ivermectin, but it also includes pyrantel pamoate, which is a medication that is effective against roundworms and hookworms. So, the main difference between Heartgard and Heartgard Plus is that Heartgard Plus contains an additional medication that is effective against roundworms and hookworms, in addition to heartworms. Heartgard Plus is often recommended for dogs that are at high risk for contracting these additional parasites or for dogs that live in areas where these parasites are common. It is important to note that neither Heartgard nor Heartgard Plus are effective against tapeworms or other types of worms, so your veterinarian may recommend additional medications to protect against these parasites. It is also important to follow your veterinarian's recommendations for administering these medications and for testing your dog for heartworms on a regular basis.

What is the safest heartworm and flea prevention for dogs?

The safest heartworm and flea prevention for dogs will depend on the individual dog and its specific needs. It is important to discuss the best options with a veterinarian, as they will be able to recommend a product that is appropriate for your dog based on its age, weight, overall health, and lifestyle. There are several heartworm and flea prevention products available for dogs, including oral medications, topical solutions, and collars. Some products may be more suitable for certain dogs, such as those that are pregnant or nursing or those with certain medical conditions. It is also important to follow the product's instructions for use carefully and to give the medication on the recommended schedule to ensure maximum effectiveness. If you have any concerns about the safety of a particular product, you should speak with your veterinarian.

What is better than Heartgard?

There are several different options available for preventing heartworm disease in dogs, and the best choice will depend on a variety of factors. Some alternatives to Heartgard include other brands of heartworm-preventive medication, such as Interceptor Plus or Trifexis. These medications are formulated to kill heartworms and other parasites and can be administered orally or topically. It is important to note that no heartworm preventive is 100% effective, and it is still possible for a dog to contract heartworms even if it is being treated with preventive medication. Therefore, it is important to follow the recommendations of a veterinarian and to regularly test your dog for heartworms to ensure that it is protected. In addition to traditional preventive medications, there are also natural options that may be effective in preventing heartworm disease. These include garlic and herbal remedies. However, the effectiveness of these natural options is not well established, and they may not provide the same level of protection as traditional preventive medications. As always, it is important to consult with a veterinarian before starting any new treatment for your dog.

Does Tri-Heart Plus cause seizures in dogs?

Tri-Heart Plus is a monthly heartworm prevention medication for dogs that contains the active ingredients ivermectin and pyrantel pamoate. It is generally considered safe and effective when used as directed. However, as with any medication, there is a potential for side effects. Seizures are a rare but possible side effect of Tri-Heart Plus. However, it is important to note that seizures can also be caused by other factors, such as underlying health conditions or other medications. If your dog experiences a seizure after taking Tri-Heart Plus, you should consult your veterinarian immediately. They will be able to determine the cause of the seizure and provide the appropriate treatment. It is also important to report any adverse reactions to the medication to the FDA.

More on Worms In Dogs

How Testing for Heartworm Changes with Lifecycle
Is Your Dog Eating Poop?
Can People Get Heartworms?

This information is for informational purposes only and is not meant as a substitute for the professional advice of, or diagnosis or treatment by, your veterinarian with respect to your pet. It has, however, been verified by a licensed veterinarian for accuracy.

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