Best Heartworm Meds for Dogs

Dog owners often struggle with choosing the right medication to safeguard their furry friends against heartworms. These parasites, transmitted through mosquito bites, pose a significant threat to dogs. In this detailed guide, we aim to help you understand and choose the best heartworm prevention medication, with insights from veterinary professionals and fellow pet owners alike.

Contents hide

Why Heartworm Prevention is Crucial

Heartworm disease, a serious and potentially fatal condition, is caused by Dirofilaria immitis, a blood-borne parasite. As its name suggests, heartworm primarily affects the heart, lungs, and blood vessels of infected dogs. With early prevention, this potentially life-threatening condition can be effectively avoided.

Vet-Recommended Heartworm Medications

Heartgard Plus for Dogs

Heartgard Plus, containing Ivermectin and Pyrantel, is a popular monthly chewable tablet. It helps prevent heartworm disease while treating and controlling roundworms and hookworms.

Interceptor Plus for Dogs

Interceptor Plus, a broad-spectrum parasiticide, combines Milbemycin Oxime and Praziquantel. It not only protects against heartworms but also eliminates adult hookworms, roundworms, whipworms, and tapeworms.

Sentinel Spectrum

Combining Milbemycin Oxime, Lufenuron, and Praziquantel, Sentinel Spectrum not only prevents heartworms but also combats multiple intestinal parasites and curbs flea populations by interrupting their life cycle.

Simparica Trio

Simparica Trio offers a three-in-one protection, combining Sarolaner, Moxidectin, and Pyrantel. This monthly chewable not only guards against heartworms but also kills ticks, fleas, and several types of intestinal parasites.

The Importance of a Vet’s Guidance

Heartworm medications are typically prescription-only. They require a veterinarian’s examination and approval to ensure your dog doesn’t already have heartworms. Administration of preventatives to heartworm-infected dogs can lead to serious complications, emphasizing the importance of a vet’s consultation.

Heartworm Medication for Dogs with Seizures

If your dog has a history of seizures, the selection of heartworm medication needs particular care. Certain oral medications, including NexGard and Bravecto, are generally contraindicated for seizure-prone dogs. Vets often recommend brands like Interceptor or Sentinel for such cases, but always consult with a veterinary professional to decide on the safest choice.

Choosing Between Chewables, Topicals, and Injectables

The choice between chewable tablets, topical treatments, or injectable medications largely depends on your dog’s preferences and lifestyle. Chewables like Heartgard Plus and Simparica Trio are convenient and often well-received by dogs. Topical treatments like Revolution (Selamectin) and Advantage Multi (Imidacloprid/Moxidectin) provide an alternative for dogs that resist oral medication. ProHeart is an injectable option, offering extended protection.

Frequently Asked Questions on Heartworm Medications for Dogs

Can I Get Heartworm Medication Without a Vet Visit?

Prescription heartworm medications should not be administered without a prior examination and approval from a veterinarian. This precaution is due to the potential complications that can occur if a heartworm-infected dog is given a preventative. However, some telemedicine platforms may facilitate a virtual vet visit for prescription renewal in specific cases.

What If My Dog Has a Heartworm Allergy?

In rare instances, dogs might exhibit allergic reactions to certain ingredients in heartworm medications. If you notice symptoms like hives, difficulty breathing, or swelling of the face, lips, tongue, or throat, contact your vet immediately. They may recommend a different formulation or brand that your pet can better tolerate.

How Do Heartworm Medications Work?

Heartworm preventatives don’t stop the initial infection from mosquito bites. Instead, they eliminate the immature heartworm larvae (microfilariae) that the dog’s body hosts after an infected mosquito’s bite. By doing this every month, they ensure that these larvae don’t mature into adult heartworms.

Are There Natural Alternatives for Heartworm Prevention?

While some pet owners might be tempted to explore natural or alternative methods for heartworm prevention, there are no scientifically validated natural substitutes for conventional heartworm preventatives. The American Heartworm Society strongly advocates for FDA-approved heartworm preventatives for effective protection.

How Often Should Heartworm Medications Be Given?

Most heartworm preventatives are designed to be given once a month, all year round, regardless of the season. Some injectable preventatives, like ProHeart, can provide protection for an extended period (6 or 12 months). Consistency in administration is vital for ensuring ongoing protection.

Can I Give My Dog Heartworm Medication If They Already Have Heartworms?

It’s crucial to have your dog tested for heartworms before starting or resuming a preventative regimen. Giving heartworm preventatives to a dog already infected can lead to severe, and sometimes fatal, reactions. If a dog tests positive, a specific treatment protocol, including adulticide and microfilaricide drugs, needs to be followed under a vet’s supervision.

Are There Risks Involved with Heartworm Medications?

Most dogs tolerate heartworm medications well. However, like all drugs, they may cause side effects in some dogs. These can range from minor digestive upset to rare, severe reactions. Certain breeds are sensitive to specific drugs due to genetic factors. Always discuss potential risks and side effects with your vet to ensure safe administration.

What are the Symptoms of Heartworm Disease in Dogs?

Heartworm disease may not show any signs until it has progressed to a severe stage. Early symptoms may be subtle, like a mild persistent cough, reluctance to exercise, or fatigue after moderate activity. As the disease advances, dogs may exhibit heart failure signs, such as swollen belly due to fluid accumulation. Severe cases can lead to life-threatening cardiovascular complications.

Can Heartworm Medication Treat Other Parasites?

Yes, many heartworm preventatives also protect against common internal parasites like roundworms, hookworms, and whipworms. Some also include protection against external parasites such as fleas, ticks, and mites. For instance, products like Simparica Trio and Sentinel Spectrum provide broad-spectrum protection against multiple parasites.

Is Heartworm Medication Necessary All Year Round?

The American Heartworm Society recommends year-round heartworm prevention, irrespective of where you live. Mosquitoes, the primary carriers of heartworms, have become increasingly adaptable and may be active during unseasonably warm periods in typically cooler months. Ensuring constant protection negates the risk of an unforeseen infection.

What If I Miss a Dose of My Dog’s Heartworm Medication?

If you forget to give your dog their heartworm preventative, give the missed dose as soon as you remember. Then, continue the regular monthly schedule. It is important to avoid missing doses, as heartworm preventatives are most effective when given consistently. If several doses were missed, consult your veterinarian before resuming medication.

Can Heartworm Medication Cause Seizures in Dogs?

Some oral flea and tick medications, including those that may also prevent heartworms, have been associated with neurological events like seizures. If your dog has a history of seizures, discuss this with your vet before starting any new medication. There may be alternatives that carry less risk for your pet.

Can Puppies Take Heartworm Medication?

Yes, puppies can and should start on heartworm preventatives as early as the product label allows, typically around 6-8 weeks of age. However, puppies under seven months of age can start on heartworm preventatives without a heartworm test (it takes about six months for a dog to test positive after it has been infected). They should then be tested six months later and yearly after that to ensure they remain heartworm-free.

How Effective Are Heartworm Medications?

When given as directed, heartworm preventatives are about 99% effective, which is why they are the best protection against heartworm disease. However, their effectiveness can be compromised if doses are skipped or delayed.

Can My Dog Develop Resistance to Heartworm Medication?

While there have been reports of suspected resistance in heartworms to certain preventatives, research is still ongoing, and conclusive evidence is yet to be found. It’s worth noting that perceived resistance often results from factors like inconsistent administration of the medication or unrecognized infections before starting the preventative.

Is Heartworm Medication Safe for All Breeds?

Most heartworm medications are safe for all breeds. However, certain breeds like Collies, Shetland Sheepdogs, Australian Shepherds, and others with a mutation in the MDR1 gene might be sensitive to the active ingredient in some heartworm medications, like ivermectin. Although these drugs are generally safe at the preventive dose level, it’s always best to consult with your veterinarian to ensure the medication is safe for your specific breed.

Are There Any Side Effects of Heartworm Medication?

Heartworm preventatives are generally well-tolerated by most dogs. Possible side effects, though rare, can include vomiting, diarrhea, lack of appetite, or lethargy. Severe reactions can occur but are incredibly rare. If your pet shows any sign of an adverse reaction or allergic response, such as facial swelling, seizures, or hives, contact your vet immediately.

Can I Use Heartworm Medication on Pregnant or Nursing Dogs?

Many heartworm preventatives are safe for use in breeding, pregnant, and nursing dogs. However, you should always consult with your vet before administering these medications to ensure they are safe for your dog in its current life stage.

How Quickly Does Heartworm Medication Work?

Heartworm preventatives work by eliminating the heartworm larvae that your dog was exposed to in the preceding month. These medications do not kill adult heartworms, nor do they have a persistent activity against future infections beyond their dosing period. This is why it’s crucial to administer these medications on a regular monthly schedule.

Can I Buy Heartworm Medication Over the Counter?

No, heartworm medications are prescription-only products. This policy is in place because a vet should test dogs for heartworm infection before starting a preventative regimen. Administering heartworm preventatives to a dog that already has the disease can lead to severe complications.

Is Heartworm Medication Necessary Year-Round?

Many veterinarians recommend year-round heartworm prevention due to the unpredictable nature of weather patterns, which can impact mosquito populations and activity. Besides, some heartworm preventatives also protect against common internal parasites, which pose a risk year-round.

Can Puppies Take Heartworm Medication?

Yes, puppies can start taking heartworm medication as early as 6 to 8 weeks of age, depending on the specific drug and your veterinarian’s recommendations. It is vital to protect puppies during their growth stage when they may be more susceptible to infections.

What if My Dog Misses a Dose of Heartworm Medication?

If you miss giving a dose of heartworm medication, give the missed dose as soon as you remember. Then, continue with the regular dosing schedule. However, it is crucial to contact your vet in this situation, as additional actions may be required to ensure your dog remains protected against heartworms.

Do Indoor Dogs Need Heartworm Medication?

Yes, indoor dogs also need heartworm prevention. Mosquitoes, which transmit heartworms, can easily get indoors, making indoor dogs susceptible to heartworm disease as well. Thus, it’s crucial to keep all dogs on a heartworm preventative, irrespective of their lifestyle.

Can Heartworm Medication Cause Diarrhea?

While most dogs tolerate heartworm medications well, some may experience gastrointestinal upset, including diarrhea, as a side effect. However, these symptoms are usually mild and short-lived. If your dog experiences persistent diarrhea after taking a heartworm preventative, consult your vet.

How Do I Know if My Dog is Allergic to Heartworm Medication?

Signs of an allergic reaction to heartworm medication can vary but may include vomiting, diarrhea, lethargy, hives, facial swelling, difficulty breathing, or seizures. If your dog exhibits any of these symptoms after taking heartworm medication, contact your veterinarian immediately.

Leave a Reply

Your email address will not be published. Required fields are marked *

Back to Top