Common Causes of Coughing in Dogs

What can cause coughing in dogs?

Healthy pets rarely cough, so a new cough is a symptom to pay close attention to. Why, though, do pets cough to begin with? Typically, coughing is a symptom that indicates a problem with the pet’s respiratory system. This may be from irritation of the lining of the airways, a weak windpipe, infection or irritation in the lungs, or pressure on the airway. Rarely, a “cough” may be from a gastrointestinal problem so it’s important to pay close attention to the type of cough your pet is displaying.

Causes of coughing can largely be classified into a few categories:

1. Infection: Infections can affect the lungs, trachea, or even the upper airway or nasal passages. This can include viral diseases, bacterial issues like pneumonia, fungal infections, or parasitic infections. Depending on the cause, the cough may sound different based on what part of the respiratory system is impacted. In “kennel cough” infections, for example, the trachea is most affected, whereas bacterial or fungal infections can cause pneumonia in the lungs.

2. Heart disease: Some heart conditions can lead to coughing as a symptom. In dogs who are diagnosed with congestive heart failure, fluid builds up in the lung tissue which causes the pet to have a wet-sounding cough. Other things such as enlargement of the heart can also cause pressure on the airways causing the dog to cough. Heartworm disease can also cause coughing when the vessels of the heart become enlarged, as well as the lung tissue becoming inflamed from the disease itself.

3. Tracheal collapse: As a typically genetic condition, some dogs have weaker rings supporting their windpipe (cartilage defect) that can cause the airway to collapse when the dog is excited or moving air quickly. This often sounds like a “honk” sound and can range from mild to severe.

4. Foreign body: In some cases, dogs will inhale something abnormal that can trigger a coughing response. This may be something like a grass awn, or a small foreign object. Esophageal foreign body objects can also trigger a cough response if large enough or not moving normally (for example, if your dog swallowed a ball) as this can press on the airway next to it as it moves down the digestive tract.

5. Cancer: Unfortunately, in some cases, the cause of coughing is from a disease such as cancer. Numerous cancer types can spread or metastasize to the lungs, causing things like small or even very large tumors. Cancer can also cause lymph node enlargement around the heart and lungs, which can cause coughing due to compression as well.

6. Airway inflammation: Conditions like bronchitis and asthma can be caused by chronic irritation or inflammation. Just as some people are sensitive to airway irritants, some pets can develop coughing from the airways being inflamed.

What are the common types of cough?

A few important traits about your dog’s cough can be very helpful in determining the cause. When did the cough start? Did it come on slowly, or all of a sudden? Is it worse with exercise? Is it worse at night or when your dog sleeps? The common types of cough seen in dogs are further described below.

Dry hacking cough -This cough is typically not “wet” sounding in nature. Often, this can be from underlying diseases like bronchitis or airway inflammation. Other causes such as compression of the airways from large blood vessels or tumors can also present this way.

Gagging cough - Often seen with inflammation in the pharynx from conditions like allergies, owners typically describe this as more of a “gag” than a cough. This type can also be misdiagnosed as a gastrointestinal issue or discomfort from acid-reflux in the esophagus.

Honking cough - Often described as a goose-honking cough, this often can be a first clue that the dog’s windpipe may be where the cough is coming from. In diseases like kennel cough and tracheal collapse, the dog’s trachea or windpipe is inflamed or weakened which results in a “honk” sound when the dog presses on their neck with a collar, or when they get excited.

“Wet” cough - Perhaps the most concerning of the types of cough described, this can often indicate serious conditions such as heart disease or pneumonia. Common concerning things with this type of cough include the dog having low energy, a decreased appetite, or the cough worsening at night or when sleeping.

How will my vet diagnose the cause of my dog’s cough?

Sometimes, your vet may diagnose your pet based on their history and physical exam alone. Often, however, they may recommend more involved testing such as:

• Bloodwork (CBC and Blood chemistry)
• Thoracic Radiographs (X-rays of the chest)
• Trans-tracheal wash (to analyze the type of cells and organisms seen in the airway)
• Parasite testing (for lungworms, heartworms, etc.)
• Echocardiogram (ultrasound) for evaluation of the heart
• EKG testing of the heart
• Serology for infectious disease
• Referral to an internal medicine specialist for specialized testing such as fluoroscopy or CT

When to See a Vet

Any time your dog develops a new cough, this is time to seek out an evaluation by a vet. If your dog is depressed, not eating or drinking, or doesn’t have nice bubble gum pink mucous membranes, or gums (instead is purple, gray, or pale) your pet should be seen urgently by a vet. Due to the possible causes ranging from mildly concerning to life-threatening, taking this symptom seriously can improve your dog’s recovery and outcome drastically. You can also monitor your dog’s respiratory rate at home by counting the number of breaths he takes when sleeping. A respiratory rate above 40 is concerning and should be evaluated urgently as well.

A note about medications:

It’s important to not give your dog any medications for their cough unless instructed by a vet. Many of these therapies can be dangerous if given for the wrong cause (such as cough suppressants for pneumonia) so getting a diagnosis for your dog’s cough before using medication is important in ensuring their safety. Your vet will help guide you in the best and safest therapies for your pet!

Read more:

Reverse Sneezing in Dogs

Causes and Treatment for Coughing in Cats

Your Pet’s Heart: A Guide to Understanding Heart Health in Dogs and Cats

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