Should I Adopt a Dog With Heartworms? Everything You Need to Know

Introduction

Walking through a shelter can be an emotional experience. You might lock eyes with a dog that seems like the perfect fit for your home. Then you see the sign on their kennel: Heartworm Positive. This diagnosis often makes potential adopters hesitate or walk away entirely. You might wonder if the dog is very sick, if the treatment is too expensive, or if they will have a shortened lifespan. These are all valid concerns for any responsible pet parent.

At GetBuddy, we believe that a medical diagnosis should not be the end of the story. Our mission is to help you find the right match for your lifestyle while providing the tools you need for a lifetime of success. This post covers exactly what heartworm disease is, how the treatment works, and what your daily life will look like during the recovery process. Adopting a heartworm-positive dog is a big decision, but with the right information, it can also be one of the most rewarding things you ever do.

Quick Answer: Yes, you should consider adopting a heartworm-positive dog if you are prepared for a few months of restricted activity and follow-up care. Most cases are fully curable, and many shelters even cover the cost of the treatment.

Understanding Heartworm Disease in 2026

Heartworm disease is caused by a parasite called Dirofilaria immitis. These worms are transmitted through the bite of an infected mosquito. Once a dog is bitten, the larvae travel through the bloodstream and eventually settle in the heart and lungs. Over time, these worms can grow up to a foot long. If they are not treated, they can cause significant damage to a dog's internal organs.

It is important to remember that heartworms are not contagious from dog to dog. Your current pets cannot catch heartworms just by being near a positive dog. A mosquito must bite an infected dog, pick up the parasite, and then bite another dog to spread the disease. In 2026, we have better tools than ever to manage this condition. While the diagnosis sounds scary, it is a very common issue in many parts of the United States.

Many dogs in shelters test positive because they were previously neglected or lived as strays without preventive medication. These dogs are often overlooked, even though they may be perfectly healthy in every other way. By choosing to adopt one, you are giving a second chance to an animal that might otherwise wait months for a home. You can begin browsing adoptable dogs while asking each rescue about its heartworm-treatment policies.

The Different Stages of Heartworm Infection

Not every heartworm-positive dog is "sick" in the traditional sense. Veterinarians categorize the infection into four classes based on how much the disease has progressed. Knowing which class a dog falls into will help you understand what kind of care they will need.

Class 1: Subclinical or Mild

In this stage, the dog usually shows no outward signs of being sick. They might have a very slight cough, but most Class 1 dogs look and act completely normal. Their blood work and X-rays often show minimal changes. This is the best time to catch the disease because the risk of complications during treatment is very low.

Class 2: Moderate

A dog in Class 2 might get tired more easily during walks or play sessions. They may have a persistent cough. When a vet looks at their X-rays, they might see some mild changes in the heart or lungs. Most dogs in this stage still have an excellent prognosis with proper treatment.

Class 3: Severe

This is a more serious stage of the disease. Dogs in Class 3 often appear thin and sickly. They may have a hard time breathing and might even cough up blood. Their activity level is very low because their heart and lungs are struggling to function. Treatment for Class 3 dogs requires much closer veterinary supervision.

Class 4: Caval Syndrome

This is a life-threatening emergency. In Class 4, there are so many worms that they physically block the blood flowing through the heart. The only way to save the dog is through a surgical procedure to manually remove the worms. This stage is rare in the adoption world because most shelters test and treat dogs long before they reach this point.

Vet Tip: Our AI Veterinarian can help you understand these stages more clearly if you have the dog's medical records. However, this tool provides AI-powered guidance and is not a substitute for an in-person consultation with a licensed veterinarian who can examine the dog.

The Treatment Process: What to Expect

The goal of treatment is to kill the adult worms and the microscopic baby worms (called microfilariae) safely. 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.

A typical treatment plan in 2026 looks like this:

1. The Preparation Phase: The dog usually begins a month-long course of an antibiotic called doxycycline. This kills a specific bacteria that lives inside the heartworms. It makes the worms weaker and easier to kill. The dog also starts a monthly heartworm preventive.
2. The First Injection: The dog receives one injection of melarsomine. This kills some of the adult worms.
3. The Final Injections: One month after the first shot, the dog receives two more injections over a 24-hour period. These shots kill the remaining worms.
4. The Testing Phase: About six to nine months after the last injection, the vet will test the dog again to confirm that all the worms are gone.

Some people talk about a "slow kill" method, which involves just giving monthly heartworm prevention. Most experts do not recommend this. It can take years for the worms to die on their own. During that time, the worms continue to damage the dog's heart and lungs. The "fast kill" method is the gold standard for a reason.

The Financial Side of Heartworm Adoption

One of the biggest hurdles for adopters is the cost of treatment. Depending on where you live and the size of the dog, professional treatment can cost anywhere from $500 to $1,800. However, many shelters and rescues in 2026 have programs to help with this. For more context on planning for medical expenses, review our pet owner financial analysis.

When you find a dog you love on GetBuddy, you can use the chat feature to ask the shelter about their heartworm policies. Many organizations will:

• Pay for the entire treatment through their own vet.
• Provide the medication at a significantly discounted rate.
• Partner with local clinics to offer low-cost care for their graduates.
• Sponsor the adoption fee to offset the future medical costs for the owner.

Don't let the potential cost stop you from inquiring. Many shelters consider these dogs "hard to place" and are very willing to work with you to make the adoption possible. Our adoption FAQ also explains how to contact rescues and submit an application.

The Most Important Rule: Exercise Restriction

If you decide to adopt a heartworm-positive dog, you must be prepared for the recovery period. This is the most challenging part for most owners. For about 6 to 8 weeks after the injections, the dog must stay extremely calm.

As the worms die, they break into pieces and pass through the dog's blood vessels to the lungs to be absorbed. If the dog's heart rate stays low, this process happens smoothly. If the dog runs, jumps, or gets too excited, the dead worm pieces can get stuck. This can cause a pulmonary embolism, which is a life-threatening emergency.

Daily life during restriction includes:

• Short, slow leash walks for potty breaks only.
• No running, wrestling, or playing fetch.
• No jumping on furniture or going up and down stairs quickly.
• Staying in a crate or a small, quiet room when you aren't home.

This might sound difficult, especially if you are adopting a young, energetic dog. However, this is where GetBuddy can help. Our AI Trainer can provide you with plenty of "brain games" and mental stimulation ideas that do not require physical exertion. Keeping a dog's mind busy can help them stay calm while their body heals.

Key Takeaway: The success of heartworm treatment depends entirely on keeping the dog calm. Exercise restriction is not a suggestion: it is a medical necessity to keep the dog alive during recovery.

How to Prepare Your Home for a Recovering Dog

Since your new dog will be on "crate rest" for a while, you need to set up a comfortable environment before they arrive. You want to make their limited space as enjoyable as possible.

Step 1: Choose a quiet location. / Place the dog's crate or bed in a low-traffic area of your home. They should still be able to see you, but they shouldn't be in the middle of a high-energy hallway or near a window where they might bark at squirrels.

Step 2: Invest in mental enrichment. / Buy plenty of puzzle toys, snuffle mats, and long-lasting chews. Since the dog cannot run, they need to use their nose and brain to burn off energy.

Step 3: Gather your supplies. / Make sure you have a sturdy leash and a well-fitting harness. You will be using the leash for every single trip outside, even in a fenced yard.

Step 4: Talk to your vet. / Some dogs are naturally high-energy and find crate rest very stressful. Your vet can prescribe mild sedatives or anti-anxiety medication to help them stay relaxed during the most critical weeks of treatment.

Long-term Outlook for Heartworm Survivors

The good news is that once the treatment is over and the dog is cleared by a vet, they can usually go back to a completely normal life. Most dogs do not have lasting complications if the disease was caught in Class 1 or Class 2. They can run, hike, and play just like any other dog.

In some cases where the infection was severe (Class 3), the dog might have some permanent scarring in their lungs or a slightly enlarged heart. They might not be able to run marathons, but they can still enjoy a very high quality of life as a beloved family member.

The most important thing you can do for a survivor is to never miss a dose of heartworm preventive again. Monthly prevention is much cheaper and safer than treatment. It is a small price to pay to ensure the disease never returns.

Is This the Right Choice for You?

Adopting a heartworm-positive dog requires a specific type of owner. You don't need to be a medical expert, but you do need to be patient. If you are looking for a dog that can go on five-mile runs the day after you bring them home, a heartworm-positive dog is not the right fit right now.

However, if you have a quieter lifestyle or are willing to commit to a few months of slow-paced living, you are the perfect candidate. These dogs are often some of the most grateful and affectionate pets. They have spent time being overlooked, and they just want a safe place to rest.

At GetBuddy, we take the guesswork out of the matching process. Our AI Lifestyle Match system looks at your daily routine and energy levels. If you tell us you have a calm home and can manage a dog with medical needs, we can help find the heartworm-positive pup that fits your world. We also provide ongoing support with our AI tools to help you navigate the training and health questions that come up during the recovery months. When you are ready, download the app today to begin matching and access those tools.

Summary of Adopting a Heartworm-Positive Dog

Adopting a dog with heartworms is a commitment, but it is one with a clear finish line. Once the treatment is done, you have a healthy, happy companion for life.

• Heartworm disease is treatable and almost always curable.
• Most shelter dogs with heartworms are asymptomatic and feel fine.
• Strict exercise restriction is the most critical part of the process.
• Many shelters provide financial assistance for the treatment.
• Post-treatment, most dogs live full, active, and long lives.

Bottom line: A heartworm diagnosis is a temporary hurdle, not a permanent label. With a little extra care and the support of GetBuddy's AI tools, you can save a life and gain a best friend.