Coughing in Dogs and Cats

Does your dog sound like it’s trying to clear its throat? Or maybe your cat is making a strange, retching sound? Coughing in pets can be alarming—but what does it actually mean?

Coughing is surprisingly complex and can be caused by a wide range of issues. Sometimes it’s linked to heart problems, but often it’s not. Even experienced vets can find it tricky to figure out the cause, especially since coughing can sound very different depending on where it’s coming from. In dogs especially, coughing can look more like gagging or retching, which only adds to the confusion.

Let’s break down the causes, what a cough actually is, when to worry, and what to do next.

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What Is a Cough?

At its core, a cough is a protective reflex designed to clear the airways of anything unwanted. Its triggered by little sensors (mechanoreceptors and chemoreceptors) in the cells that line the airways.

• It starts with a deep breath in.
• Then the vocal cords (glottis) close tightly.
• The chest and abdominal muscles contract.
• Suddenly, the glottis opens, releasing a burst of air—and hopefully whatever was irritating the airway.

This can be triggered by:

• Dust, smoke, or irritants in the air
• Mucus or secretions from the body
• Foreign bodies (like food or small objects)
• Infections (viral, bacterial, parasitic)

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Two Types of Reflexes Involved in Coughing

Understanding the difference can help make sense of the sounds your pet is making.

1. Cough Reflex (CR)

• Triggered deeper in the airway (trachea and bronchi)
• Involves a deep breath in first
• Helps clear things, particularly secretions, that are lodged deeper down
• The deep breath in first gives more power to the expulsive effort.

2. Expiratory Reflex (ER)

• Triggered higher up, near the voice box (larynx)
• A quick, sharp puff of air without breathing in first
• Often sounds like a ‘huff’ or a gagging/retching noise
• Much better at protecting the airways from something trying to go ‘down the wrong way’
• Avoiding a deep breath in first reduces the risk of it getting deeper…

These reflexes are triggered by special sensors in the airway, and they can become overly sensitive—especially after infections or inflammation—leading to a lingering cough even after the original issue has passed. Dogs seem especially prone to the expiratory reflex, and this is commonly seen with infectious diseases (like ‘kennel cough’) and with more chronic airway degenerative diseases.

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Common Causes of Coughing in Dogs vs. Cats

Dogs

• Older dogs often develop weakened or collapsing airways with age.
• Chronic bronchitis, airway infections, or “kennel cough” are common.
• Smaller dogs are more likely to develop coughing due to enlarged hearts pressing on the airways.

Cats

• Feline asthma is a major cause—a condition similar to human asthma, often triggered by environmental allergens.
• Cats are less prone to coughing with heart disease, and when they do, it’s often not a heart-related issue.

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Coughing and Heart Disease

Can Heart Problems Cause Coughing?

Yes—but it’s not always straightforward.

• Dogs with enlarged hearts (cardiomegaly) may cough if their heart presses on weakened airways.
• This is especially true in small, older dogs with mitral valve disease. This is because mitral valve disease causes the heart to have to beat much more powerfully and dynamically than before.
• However, not all pets with heart disease will cough.
• In fact, many pets in congestive heart failure (CHF) don’t cough at all.

Why Not?

• CHF causes fluid to leak into the lungs, which is very serious.
• But the deep parts of the lungs don’t have many cough receptors.
• So a cough only happens if fluid moves higher up—by that point, other signs are often already severe.

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So, Is Coughing a Sign of Heart Failure?

Not reliably.

It may point to:

• Heart enlargement
• Aging or collapsing airways

But it’s not a reliable indicator of CHF.

More important signs include:

• Fast or labored breathing at rest
• Lethargy or poor appetite
• Collapse or fainting spells

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🫁 Sleeping Respiratory Rate (SRR): The Key Sign

• Count how many breaths your pet takes in one minute while sleeping.
• More than 30 per minute is a warning sign—especially in pets with known heart disease.
• See our dedicated post on SRR for how to monitor it at home.

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What about lung cancer?

Sadly, although lung cancer is much less common in dogs and cats than in people, it is still something we see.

• If the cough seems to be worsening over time.
• And especially if there are signs that your pet is unwell in other ways, such as losing weight.
• Then getting imaging done of the airways (eg an X-ray) is probably highly important.

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When to Seek Veterinary Help

Sudden Onset Cough

• With known heart disease or murmur: Monitor breathing closely. If SRR > 30, contact your vet urgently.
• Without known heart issues: Still monitor SRR. If breathing is rapid, labored, or your pet seems distressed, it could be:
  • Pneumonia
  • Asthma (especially in cats)
  • Airway obstruction or irritation

If breathing is normal and your pet seems comfortable, it might be a mild infection such as kennel cough—but it’s always best to get it checked.

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Persistent or Chronic Cough

• Dogs: Likely due to airway disease or collapse, especially with age. Still, heart disease could be contributing, so rechecking the heart may be wise.
• Cats: Most chronic coughs are caused by asthma. If your cat has heart disease, a new cough probably doesn’t mean worsening heart failure—but always watch for changes in breathing rate and effort.

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Final Thoughts

A coughing pet isn’t always a medical emergency—but it’s rarely something to ignore either.

• Monitor breathing closely, especially during rest.
• Keep track of patterns: Is it worse at night? After exercise? In certain environments?
• Talk to your vet, especially if the cough is new, persistent, or associated with any changes in breathing, appetite, or energy levels.

Remember: coughing can be caused by the heart, the lungs, the airways—or a mix of all three. Diagnosing the true cause often needs careful investigation.

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