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10 Heartworm Prevention Mistakes In Dogs That You May Be Making

10 Heartworm Prevention Mistakes In Dogs That You May Be Making

Here we will discuss the 10 heartworm prevention mistakes in dogs that you may be making. Read on to learn more.

Heartworms are common in dogs of all breeds, including doodles. They are among the most damaging parasites in doodles, but they are almost 100 percent preventable.

Unlike external parasites like ticks and fleas, you cannot see heartworms on your furry friend.

When heartworm symptoms become apparent, it is often too late for your furry friend to fully recover.

That is why prevention is the only way to protect your pet against the dangers of heartworm disease truly.

What Is Heartworm Disease?

Heartworm disease is an invisible but potentially fatal disease in dogs and other animals. The heartworm in dogs prevalent in the United States goes by the scientific name Dirofilaria immitis or D. immitis.

A parasitic worm can infect your pet through a mosquito bite. It is a large worm, reaching a foot or more in length.

As it completes its life cycle, which takes about seven months, it ends up in the heart and pulmonary vessels, where it can live for several more years.

After about a year, your dog may harbor hundreds of these worms, although 15 is the average burden.

Heartworm Prevention Mistakes

Symptoms Of Heartworm In Dogs

Heartworm symptoms can vary depending on the severity of the infection and the stage of the disease. In the early stages, there may be no signs of disease.

However, as the worms grow and multiply, symptoms will become evident, increasing in severity as the disease progresses.

There are four classes of heartworm infection in dogs.

Class One

This is the first stage of heartworm infection in dogs. It has no symptoms or just a mild cough or fatigue after exercise. X-rays and diagnostic tests may show minimal lung and heart involvement.

Class Two

Dogs in this infection stage have moderate heartworm disease. They start showing noticeable symptoms.

The stage is marked by mild exercise intolerance and persistent cough. Other signs include occasional difficulty breathing and fatigue.

X-rays and diagnostic tests reveal more pronounced lung and heart involvement than Class One.

Class Three

Doodle dogs in this stage have severe heartworm infections. Clinical signs are more severe and obvious in this stage.

The common symptoms include persistent coughing, exercise intolerance, swollen abdomen due to heart failure, weight loss, and difficulty breathing.

Your furry friend may also have pale gums, abnormal lung sounds, and decreased appetite.

Class Four

Class four is the last stage of heartworm infection, characterized by highly compromised health. Dogs in this stage have very severe heartworm disease.

Your furry friend may exhibit all the symptoms mentioned in Class Three, but they will be more severe.

They may experience caval syndrome, a life-threatening cardiovascular collapse marked by labored breathing, pale gums, and dark coffee-colored urine, leading to complete organ failure and death.

It is important to note that while the symptoms above can all be seen with heartworm disease, they are also seen in other conditions.

So it is always important to see your vet if you suspect your furry friend has heartworm disease. Also, heartworm symptoms may not be seen in puppies under six months old.

How To Prevent Heartworm Disease In Dogs

The following are ways to prevent heartworm disease in dogs.

Regular Check-ups

Regular vet check-ups are important for your dog’s overall health monitoring, including heartworm prevention.

Your vet can guide you on the most suitable preventive medication for your furry friend’s needs and perform necessary tests.

Preventive Medications

One of the most common and best methods of heartworm disease prevention in dogs is the administration of preventive medications.

The medications come in various forms, such as chewable tablets, injectables, and topical treatments.

Preventive medications kill immature heartworm larvae that may have been transmitted to your furry friend during mosquito bites.

When administering heartworm preventive medications, you will want to follow the dosage instructions provided by your vet. Also, be sure to administer the preventative medication consistently, year-round.

Annual Testing

Just because your dog is on preventive medication does not mean they will never suffer from heartworm disease. Even if your furry friend is on preventative medicine, annual heartworm testing is recommended.

Annual testing can help detect the presence of adult heartworms and ensure your furry friend is not infected. Early heartworm detection in dogs allows for prompt treatment if necessary.

Avoid Mosquito Exposure

Mosquitoes are the primary carriers of heartworm disease. Therefore, you can reduce the risk by minimizing your furry friend’s mosquito exposure.

You will want to avoid outdoor activities during peak mosquito times (usually dusk and dawn). You should also have windows and doors screened and use mosquito repellents approved for dogs.

Heartworm Prevention Mistakes

Heartworm Prevention Mistakes That You May Be Making

The following are the common heartworm prevention mistakes most people make.

Delaying the Start of Prevention

Some dog keepers may wait until mosquito season is in full swing before starting heartworm prevention, putting their furry friends at risk.

It takes time for the preventive medication to build up in your pet’s system and provide adequate protection.

Therefore, you will want to start prevention before mosquito season begins. Your vet can also advise the right time to start prevention medications.

Inconsistent Administration

Irregular or inconsistent administration of heartworm preventive medication is one of dog owners’ most common mistakes.

Heartworm preventives are typically administered monthly, so it is crucial to administer them on time, every time.

When you miss a dose or administer it irregularly, you can leave your furry friend vulnerable to heartworm infection.

Using Wrong Medications

Various heartworm preventives are available, including injectables, oral medications, and topical treatments.

Using the appropriate preventive medicine for your pet’s age, size, and health condition is crucial. You may want to consult your vet to determine the most suitable option.

Ignoring Weight Changes

Heartworm preventive medications are typically administered based on the dog’s weight. Therefore, if your furry friend experiences significant weight changes, consult your vet to ensure the appropriate dosage.

Irregular Testing

Testing your dog annually for heartworm disease is vital, even when they are on preventive medication.

It helps detect any potential infections and allows prompt treatment. Delaying or skipping testing can lead to further complications.

Not Following Up After Missed Doses

You may miss administering medications if you are often busy with other chores. If you accidentally miss a dose of heartworm preventive medication, consult your vet for guidance on what steps to take.

Expiry Dates

It is always advisable to check the expiry date on all medications before administering them.

Expired medicines may not be practical, leaving your furry friend vulnerable. It can also be harmful to your dog’s health.

Lack of Veterinary Guidance

No matter how experienced you are, you should always consult your vet for proper heartworm disease prevention.

Your vet can provide personalized recommendations based on the dog’s specific needs and the prevalence of heartworm disease in your location.

Heartworm Prevention Mistakes

Frequently Asked Questions

What are the effects of heartworms in dogs?

Heartworms can cause severe damage to your dog’s lungs, heart, and associated blood vessels. The common signs of the condition include coughing, less loss, difficulty breathing, and lethargy.

What are the first signs of heartworm in dogs?

Heartworm symptoms in dogs may not show immediately. The first signs may include reluctance to exercise, decreased appetite, a mild persistent cough, and fatigue after moderate activity.

Can heartworms be passed from dog to dog?

Your dog cannot contract heartworm through contact with dogs. Instead, heartworm disease can only be spread through the bite of a mosquito.

Why is my dog vomiting after heartworm treatment?

If your furry friend is diagnosed with heartworm disease, the treatment administered by your vet to kill the worms may be associated with side effects, such as vomiting.

However, dogs have many causes of vomiting, so it is good to contact your vet if your furry friend is vomiting after heartworm treatment.

Why is my dog coughing after heartworm treatment?

Heartworm treatment kills worms in the lungs’ blood vessels and can result in significant inflammation, leading to coughing.

Can I treat heartworms at home?

Heartworm disease is dangerous and is not something to treat by yourself. While you can treat your dog at home, get help from a professional.


Heartworm is a potentially deadly parasite in dogs transmitted only by mosquitoes.

The common symptoms include coughing, difficulty breathing, lethargy, exercise intolerance, weight loss, and sudden death.

While treatments are available for dogs, prevention is the wisest approach to dealing with heartworms.

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