Coughing in dogs can be as concerning as it is confusing. One moment your dog seems perfectly fine, and the next, they’re producing a persistent, dry hack or a soft, chronic wheeze. Two of the more common causes of canine cough are kennel cough and heartworm disease, but they are fundamentally different conditions that require completely different approaches.
At Metrovet Veterinary Clinic in Boston, we frequently evaluate coughing dogs to determine the cause and provide appropriate treatment. Whether the culprit is infectious or parasitic, early detection is key to managing symptoms and improving outcomes.
This article is intended for informational purposes only and is not a substitute for professional veterinary advice, diagnosis, or treatment. If your dog is coughing, we recommend scheduling an appointment with your veterinarian.
Understanding Kennel Cough: The Basics
Kennel cough, or canine infectious tracheobronchitis, is a contagious respiratory disease caused by a combination of viruses and bacteria. The most common culprit is Bordetella bronchiseptica, often working in tandem with canine parainfluenza or adenovirus. The disease spreads easily through airborne droplets, direct contact, or contaminated surfaces, making places like dog parks, grooming salons, boarding kennels, and daycare facilities high-risk environments.
The hallmark symptom of kennel cough is a sudden, loud, dry, honking cough that almost sounds like your dog is trying to clear their throat. Many pet parents describe it as similar to a goose honk. Dogs may also experience mild lethargy, sneezing, nasal discharge, or a low-grade fever, but otherwise they often appear relatively normal and maintain a healthy appetite.
In most cases, kennel cough is self-limiting and resolves within 1-3 weeks. However, in puppies, senior dogs, or immunocompromised pets, the infection can become more serious and may progress to pneumonia if left untreated.
Recognizing Heartworm Disease and Its Respiratory Signs
Heartworm disease is a potentially fatal condition caused by Dirofilaria immitis, a parasitic worm transmitted through mosquito bites. Once inside the body, the larvae travel through the bloodstream and mature into adult worms in the heart, lungs, and associated blood vessels. Over time, these worms cause severe damage to the cardiopulmonary system, leading to lasting health consequences.
Unlike kennel cough, the cough associated with heartworm disease tends to be softer, more chronic, and often worsens with exercise. It’s not an abrupt, loud sound but rather a gentle, dry cough that may be accompanied by signs of fatigue, weight loss, decreased appetite, or even fainting in severe cases.
Heartworm disease develops slowly, and symptoms usually don’t appear until the infestation is well established. That’s why regular screening and preventive medication are so crucial. In Boston, where mosquito season is increasingly unpredictable due to climate changes, year-round prevention is a smart and necessary safeguard.
Key Differences in the Coughs
One of the most confusing things for dog owners is that both kennel cough and heartworm disease present with coughing. But several characteristics help set them apart:
Kennel cough is sudden in onset. Dogs seem fine and then start coughing noticeably, often after a visit to a high-traffic pet facility. The cough is harsh and sounds like a honk or gag, frequently triggered by excitement or pressure on the trachea (such as pulling on a collar).
Heartworm cough, on the other hand, creeps in gradually. It’s usually less forceful and more persistent. You might notice it after exercise or when your dog is resting. It’s often accompanied by subtle signs of systemic illness rather than localized respiratory irritation.
How Vets Diagnose Each Condition
Veterinarians rely on clinical signs, physical exams, history, and diagnostic tests to determine the cause of your dog’s cough. For kennel cough, diagnosis is typically based on presentation and recent exposure. Chest x-rays may be used if complications are suspected, but many dogs recover with supportive care alone.
Diagnosing heartworm disease requires a blood test to detect adult female heartworms. If the test is positive, further imaging such as chest radiographs or echocardiography may be used to assess the severity and determine treatment plans. Because heartworm treatment is complex and carries risks, accurate diagnosis and staging are essential.
Treatment Options and Management Strategies
Treatment for kennel cough often includes rest, hydration, and sometimes antibiotics if a bacterial infection is confirmed or suspected. Cough suppressants may be prescribed in cases where the coughing interferes with sleep or quality of life. Most dogs recover without complication, though isolation is important to prevent spreading the illness to other dogs.
Heartworm treatment, by contrast, is far more intensive. Dogs diagnosed with heartworm disease must undergo a carefully managed protocol involving heartworm-killing injections, exercise restriction, and anti-inflammatory medications. The treatment can span several months and comes with a risk of complications from dying worms lodging in the lungs or vessels. This is why prevention is always the better path.
Prevention Is the Best Medicine
Both kennel cough and heartworm disease are largely preventable with the right strategies. Vaccination plays a key role in protecting against kennel cough, particularly for dogs that spend time in social settings. While the vaccine doesn’t guarantee complete immunity, it significantly reduces the severity and spread of infection.
For heartworm, monthly preventives—whether chewable tablets, topical solutions, or injections—are extremely effective. Skipping doses or assuming your dog is safe in cooler months can lead to dangerous gaps in protection. At Metrovet, we offer year-round prevention plans that fit your dog’s lifestyle and local risk factors.
When to Worry and When to Act
Any persistent or unexplained cough should be brought to your veterinarian’s attention. While kennel cough may seem minor, it can progress or mask more serious issues. Heartworm disease, though more insidious in its onset, poses long-term health risks and requires immediate attention once diagnosed.
Watch for changes in your dog’s energy levels, breathing patterns, appetite, or behavior. If your dog has recently been exposed to other dogs, has missed heartworm prevention, or is showing systemic signs along with coughing, don’t wait. Prompt evaluation can mean the difference between a simple recovery and a more serious health crisis.
Conclusion
Understanding the nuances between kennel cough and heartworm-related cough helps you make informed decisions about your dog’s care. While they may sound similar at first, the underlying causes, progression, and treatments are entirely different. Listening closely to your dog’s body language, behavior, and breathing can offer important clues—and your veterinarian will take it from there.
If your dog has started coughing and you’re unsure why, don’t rely on guesswork or wait it out. Schedule a visit and let us help guide you to answers, relief, and a healthy outcome for your four-legged family member.
