Should I Adopt a Dog That Is Heartworm Positive?

Introduction

You are browsing through adoption listings or walking through a shelter when you see a dog that stops you in your tracks. They have the perfect energy, the right size for your home, and they look at you with an immediate connection. Then you notice the medical note: heartworm positive. For many potential adopters, those two words feel like a stop sign. You might worry about the cost, the health risks, or whether you are equipped to handle a sick animal.

At GetBuddy, we see this situation often. Heartworm disease is a serious condition, but it is also treatable. Adopting a heartworm positive dog is a brave and compassionate choice that often saves a life, especially since these dogs stay in shelters longer than their healthy peers. This guide will walk you through what the diagnosis really means, how treatment works, and how to manage the recovery period. Heartworm status is a chapter in a dog's life, but it does not have to be the whole story.

Quick Answer: Yes, you should consider adopting a heartworm positive dog if you can commit to several months of exercise restriction and follow-up medical care. Most dogs go on to live full, healthy lives after completing the treatment, and many shelters cover the initial costs of the medication.

What Heartworm Disease Actually Is

Heartworm disease comes from a parasite called Dirofilaria immitis. These worms are spread exclusively through the bite of an infected mosquito. They cannot be passed directly from dog to dog. When a mosquito bites an infected animal, it picks up microscopic baby worms. When that same mosquito bites your dog, it leaves those larvae behind.

Over the course of about six to seven months, those larvae grow into adult worms. They eventually settle in the heart, lungs, and surrounding blood vessels. If left untreated, these worms can grow up to a foot long. They multiply and begin to physically block the flow of blood. This can lead to lung disease, heart failure, and damage to other organs like the liver and kidneys.

In 2026, we have very clear ways to identify and treat this. Most shelters test every dog upon intake. If a dog is heartworm positive, it simply means they have adult worms present in their system. It does not necessarily mean the dog is currently "sick" or showing symptoms. Many dogs in the early stages of the disease act completely normal.

The Four Stages of Heartworm Disease

Veterinarians classify the disease into four classes based on how much the infection has progressed. Understanding these stages helps you know what to expect during the adoption process.

• Class 1: This is the earliest stage. The dog often shows no symptoms at all. A simple blood test is the only way to know the worms are there.
• Class 2: The dog might show mild symptoms. You may notice an occasional cough or see that they get tired a little faster than usual during a walk.
• Class 3: This is a more severe stage. The dog may look thin, have a persistent cough, or have significant trouble breathing. You can often see clear signs of heart and lung damage on an x-ray.
• Class 4: This is also known as caval syndrome. This is a life-threatening emergency where the mass of worms is physically blocking blood from leaving the heart. It usually requires surgery to remove the worms.

Most dogs available for adoption are in Class 1 or 2. Shelters work hard to stabilize dogs before they even list them for adoption. If you find a dog you love on GetBuddy, you can chat directly with the shelter staff to ask exactly which stage the dog is in and what diagnostic tests they have already performed. For general questions about matching, applications, and rescue communication, review our adopter FAQ.

The Treatment Process Explained

The goal of treatment is to kill the adult worms safely while minimizing the risk of complications. The American Heartworm Society recommends a specific protocol often called the "fast kill" method. This involves a series of injections of a medication called melarsomine.

The process usually follows a structured timeline. First, the dog is often started on an antibiotic called doxycycline. This kills a specific type of bacteria that lives inside the heartworms. Weakening the bacteria makes the heartworms more vulnerable to the treatment. At the same time, the dog starts on a monthly heartworm preventive.

The actual injections happen in stages. Most veterinarians use a three-dose protocol. The dog gets one injection, followed by a month of rest. Then, they receive two more injections 24 hours apart. These injections are deep muscle shots. They can be painful, so your vet might prescribe pain medication or anti-inflammatories to keep the dog comfortable.

The Importance of Exercise Restriction

The hardest part of heartworm treatment is not the medicine. It is the rest. When the medication kills the adult worms, they begin to break apart and dissolve. These pieces of the worms are carried by the bloodstream into the lungs to be filtered out by the body.

If a dog’s heart rate increases through running, jumping, or excitement, those worm fragments can get lodged in the blood vessels. This can cause a pulmonary embolism, which is a life-threatening blockage.

For about six to ten weeks during and after the injections, the dog must stay extremely calm. This means:

• No running or playing in the yard.
• Leash walks only for potty breaks.
• No jumping on furniture.
• Limited excitement when guests arrive.
• Often, keeping the dog in a crate or a small, quiet room when you are not home.

Key Takeaway: Success in heartworm treatment is 20% medicine and 80% management. Your primary job as an adopter is keeping your new friend calm while their body clears the dead worms.

Managing the Costs of Adoption

One of the biggest concerns for adopters is the price tag. Heartworm treatment is not cheap. Depending on your location and the size of the dog, the full treatment protocol can cost anywhere from $500 to $1,800. Larger dogs require more medication, which increases the cost.

However, the rescue community knows that the cost is a barrier. Many shelters and rescues will pay for the entire treatment if you adopt the dog. Some may have already completed the injections before the dog goes home. Others will send you home with a "foster-to-adopt" agreement. In this setup, the rescue pays for the vet visits at their partner clinic until the dog tests negative. Once the dog is clear, the adoption is finalized.

When you use GetBuddy to find a pet, check the listing details or use the chat feature to ask about medical sponsorships. Many organizations have dedicated funds specifically for heartworm-positive dogs. For additional context on adoption expenses, explore this guide to the costs of adopting a dog.

Insurance and Future Care

It is important to know that most pet insurance companies will consider heartworm disease a pre-existing condition. They will likely not cover the cost of the initial treatment if the dog was diagnosed before the policy started.

However, once the dog has successfully completed treatment and tested negative, they are essentially "cured." You should still be able to get insurance for other health issues. In the long run, the only extra cost is the monthly heartworm preventive medication. This is a cost every dog owner should have anyway, as prevention is much cheaper and safer than treatment.

Life During Recovery: Keeping Your Dog Happy

How do you keep a frisky dog calm for two months? This is where many adopters feel overwhelmed. If you adopt a young, high-energy dog, the idea of "crate rest" feels like a nightmare.

This is a great time to focus on mental stimulation rather than physical exercise. Since the dog cannot run, you have to make their brain work.

1. Lick Mats and Puzzle Toys: Use slow feeders or Kongs filled with frozen peanut butter. This keeps them occupied for 30 minutes without raising their heart rate.
2. Scent Work: Hide treats in a rolled-up towel or around a small room and let them find them. Sniffing is a low-impact activity that tires dogs out mentally.
3. Basic Training: This is a perfect time to work on "stay," "paw," or "look at me." These commands don't require movement but build a strong bond between you and your new pet.
4. Gentle Massage: Soft touch can help lower a dog’s stress levels and keep them calm.

Vet Tip: Our AI Trainer can provide specific suggestions for low-energy games and mental enrichment to help you get through the recovery period. While the AI Trainer is a great resource for ideas, always talk to your veterinarian if your dog seems excessively restless or anxious, as they may need mild sedation to stay safe during treatment.

Long-Term Outlook for Heartworm Positive Dogs

The good news is that the vast majority of dogs who complete heartworm treatment go on to live completely normal lives. Unless the dog was in Class 3 or 4 and suffered significant permanent damage to their heart or lungs, there are usually no lasting effects.

Once the dog tests negative (usually about six months after the last injection), they can return to full activity. They can go for hikes, play fetch, and run at the dog park just like any other dog.

The most important thing to remember is that a dog can get heartworm again. Successful treatment does not provide immunity. You must commit to giving a monthly heartworm preventive for the rest of the dog's life. These preventives are very effective and are usually a simple flavored chewable tablet.

Is This the Right Choice for You?

Adopting a heartworm-positive dog is a specific kind of commitment. It is not just about the money; it is about the time and the environment you can provide.

You might be a great fit if:

• You have a relatively quiet home without a lot of chaos or high-energy activity.
• You are willing to be diligent about leash walks and crate rest.
• You are looking for a dog to bond with through quiet time and training.
• You have access to a veterinarian you trust.

You might want to reconsider if:

• You have a very active lifestyle and want a dog to go running with immediately.
• You have young children or other high-energy pets that will make it impossible to keep the new dog calm.
• You do not have the time to supervise the dog's activity levels for several weeks.

At GetBuddy, we want every match to be a forever match. Our AI Lifestyle Match system helps you find a dog that fits your actual daily routine. If you indicate that you are willing to manage a medical condition like heartworm, we can help connect you with incredible dogs who are often overlooked just because they need a little extra help at the start. Learn more about how lifestyle matching supports successful adoptions.

Vet Tip: If you are ever worried about your dog's breathing, lethargy, or cough during the recovery phase, contact your vet immediately. Our AI Veterinarian is available 24/7 to help you understand common recovery signs or help you decide if a symptom needs a vet visit. Remember that AI guidance is for peace of mind and general information; it never replaces the diagnosis and hands-on care of your local veterinarian.

Preparing Your Home for an HW+ Dog

If you decide to move forward, preparation is key. You want to have everything ready before you bring your new friend home so the transition is as low-stress as possible.

• Step 1: Set up a "Quiet Zone." Choose a corner of the house that doesn't get a lot of foot traffic. Put a comfortable bed there and a crate if the dog is crate-trained.
• Step 2: Gather "Boredom Busters." Stock up on chew toys, lick mats, and long-lasting treats.
• Step 3: Consult your Vet. Schedule an appointment for a few days after you bring the dog home. Bring all the medical records from the shelter so your vet can review the timeline and plan the next steps.
• Step 4: Establish a Routine. Dogs feel more secure when they know what to expect. Keep meal times and potty breaks consistent to keep their stress levels low. This step-by-step adoption guide can help you prepare for the transition into your home.

The Reward of Saving an "Overlooked" Pet

There is something special about the bond formed with a dog you have nursed back to health. Many people who adopt heartworm-positive dogs find that the quiet recovery period actually helps them build a deeper connection. Because you have to spend so much time just "being" with the dog rather than "doing" with the dog, you learn their personality, their quirks, and their non-verbal cues very quickly.

Shelters across the US, especially in the South, deal with high rates of heartworm. In 2026, many of these shelters are still struggling with overcrowding. When you choose to adopt a heartworm-positive dog, you are freeing up space for another animal in need. You are taking a dog that might have stayed in a kennel for months and giving them a quiet place to heal. Read more about the dog adoption process and what to expect.

Bottom line: Heartworm disease is a hurdle, not a finish line. With the right care and a little patience, an HW+ dog will be just as fast, fun, and loving as any other pet.

Conclusion

Adopting a heartworm positive dog is an act of incredible kindness that rewards you with a loyal companion. While the diagnosis sounds intimidating, the treatment is highly successful, and the recovery period is manageable with a bit of planning. By providing a calm environment and following veterinary guidance, you can help a dog transition from "at-risk" to "healthy and happy."

• Heartworm is treatable and most dogs recover fully.
• The recovery period requires 6-10 weeks of strict exercise restriction.
• Many shelters provide financial assistance for the treatment costs.
• Monthly prevention is essential to keep the dog healthy for life.

If you are ready to open your heart to a dog that needs a little extra care, download the app today. Our AI Lifestyle Match can help you find a dog whose personality and needs fit perfectly with your home, and our AI Vet and Trainer will be there to support you every step of the way through the recovery process and beyond.