Coughing in dogs – causes and when to contact a vet

Coughing in dogs can be caused by anything from a mild, contagious respiratory infection to disease of the trachea, bronchi, lungs or heart. What the cough sounds like, how long it has lasted, and whether the dog has other symptoms, provide important clues as to what the cause is – and how quickly the dog should be examined.

What can cause coughing in dogs?

Coughing in dogs is a reflex that is meant to clear mucus, foreign bodies or irritation from the respiratory tract. It can come from the throat, trachea, bronchi or the lung tissue itself, and is therefore a non-specific symptom. What differentiates the causes is the age of the dog, how long the cough has lasted, what it sounds like, and what kind of signs are present.

Kennel cough and other respiratory infections

Kennel cough is not a single disease. The term is used to describe a complex disease picture – canine infectious respiratory disease complex – where several infectious agents may be involved, including bacteria Bordetella bronchiseptica, parainfluenza virus and adenovirus type 2. The infection spreads easily through close contact, droplets and objects shared by dogs.

Typically, the cough comes on suddenly, is dry and forceful, and often ends with vomiting or burping. Many dogs are otherwise alert and eat normally. The cough can persist for a couple of weeks even when the course is uncomplicated.

There's vaccines that cover some of the infectious agents. They can reduce the risk of disease and make the course milder, but they do not protect against all causes of kennel cough. A vaccinated dog can therefore still get sick. You can find out more about the course and treatment in our article about kennel cough.

Chronic bronchitis

Chronic bronchitis is a persistent inflammation of the lower respiratory tract and one of the most common causes of prolonged coughing in dogs. The cough is often dry and harsh, comes in fits, and has often persisted for months before being brought to the veterinarian's attention. The dog may otherwise appear healthy, but may become easily fatigued.

Tracheal collapse

In tracheal collapse, the cartilage in the windpipe is weakened, causing the windpipe to flatten when the dog breathes. The condition is particularly common in small and toy breeds, and often causes a dry, harsh cough that many describe as a goosebump.

The cough is typically triggered or worsened by excitement, heat, eating, drinking, or pressure from a collar on the neck. Using a harness instead of a collar is a simple measure that often helps in everyday life.

Foreign bodies and lungworms

A foreign body in the airways often has an abrupt onset: the dog suddenly coughs violently and persistently, often right after sniffing or jumping in tall grass. Blades of grass and ears of corn are a classic cause, because they have barbs that allow them to only move inwards. This should always be investigated – it does not go away on its own.

Some lungworms, such as Crenosome vulpis, can also cause coughing and reduced stamina. How relevant it is is assessed based on, among other things, where the dog has been, whether it hunts or eats snails and small rodents, and what other symptoms it has.

Short-nosed dogs and narrow airways

In short-nosed breeds, it is most often the upper airways that are narrow. This usually causes noisy breathing, snoring, vomiting and gulping, reduced stamina and poor heat tolerance. Coughing may occur, but is rarely the main sign. In these dogs, it is worth having a BOAS grading, which describes how much breathing is actually affected.

Heart disease

Heart disease can cause coughing, including fluid in the lungs or an enlarged heart pressing on the airways. However, coughing alone does not mean that the dog has heart failure. In an older, small dog with a heart murmur, chronic bronchitis or tracheal collapse is often a more likely explanation than heart failure, as long as the dog's breathing is not affected.

What shifts suspicion towards the heart is the combination of signs: increased breathing rate at rest, reduced endurance, heavier breathing at night and a heart that changes over time. If suspected, we do a targeted heart examination with ultrasound of the heart.

Tumors and other causes

In older dogs, tumors in the lungs or chest cavity must also be considered, whether they have originated there or have spread from another location. Disease of the throat, such as laryngeal paralysis in older, larger breed dogs, can cause coughing along with altered barking and noisy inhalation. Dogs that choke when eating or drinking may cough because food or liquid has entered the airway.

Is it coughing, hoarseness or inverse sneezing?

Many owners are unsure of what they are actually seeing, and that is understandable – the sounds are similar. However, the distinction is important, because they point to different parts of the airway.

• Reap is a forceful exhalation from the trachea and bronchi, often with an open mouth and stretched throat.
• sneezing quickly pushes the air out through the nose.
• Reverse sneezing are more fast, powerful inhalation with a snoring or sniffling sound. The dog often stands still with his neck stretched out. It looks dramatic, but is a completely different reflex than coughing, and is caused by irritation in the nose and throat. If you see this often, it is worth reading about nose mite in dogs.
• Vomiting and retching often comes right after a coughing fit, and is easily confused with the dog vomiting.

Feel free to record a short video with your phone when your dog has a seizure. Sounds are difficult to describe afterwards, and a ten-second video often gives us more information than a long explanation.

What can you watch at home?

While you are waiting for an appointment, or considering whether it is urgent, there are a few things that provide a lot of information.

• Breathing rate at rest. Count the breaths while the dog is sleeping or completely relaxed. One inhalation and exhalation counts as one breath. In a sleeping dog, the rate is usually below 30 breaths per minute. If it is repeatedly above this, especially in conjunction with coughing, reduced endurance or heavier breathing, a veterinarian should be contacted. Dogs with known heart disease are often told to monitor this measurement at home.
• General condition and appetite. A dog that is awake, eating, and wants to go out is in a different situation than one that stays down.
• Temperature. Rectal temperature can provide useful information, but a normal temperature does not rule out illness, and stress can affect the measurement. See how to measure temperature correctlyBreathing and general condition weigh more heavily than the number on the thermometer.
• Calm and harness. Limit hard runs and play while your dog is coughing, and use a harness instead of a collar to avoid pressure on the windpipe.
• Infection considerations. If a contagious respiratory infection may be the cause, the dog should be kept away from close contact with other dogs as long as it has symptoms.
• Do not give cough medicine intended for humans. Several of them contain active ingredients that should not be used in dogs, and cough suppressants can also be directly harmful if the dog has an infection or a foreign body.

When should a veterinarian be contacted?

Contact a veterinarian immediately if the dog is clearly breathing with effort, has rapid breathing at rest along with signs of illness, develops bluish or gray mucous membranes, collapses or becomes very weak, coughs up blood, or is unable to calm down after a seizure.

make an appointment soon if the dog is a puppy or older, has known heart or lung disease, has a fever, is lethargic or is not eating well, or if the cough becomes more frequent, stronger or shows no signs of improvement.

We deliberately do not use a fixed limit of two weeks. A mild kennel cough can last for a while in an otherwise healthy adult dog, while pneumonia or a foreign body should not be considered at all. It is the severity, development and additional symptoms that determine - not the calendar.

How is a coughing dog examined?

The investigation is built up step by step, and how far we go is governed by what we find along the way.

• Medical history. When did the cough start, what does it sound like, has the dog been with other dogs, been traveling, or has it coughed before?
• Clinical examination. We listen to the lungs and heart, feel the throat and trachea, assess the mucous membranes and measure the respiratory rate.
• Chest X-ray as needed. This is often the most important single step, because it distinguishes between pneumonia, fluid in the lungs, enlarged heart, tumors, and normal lungs.
• Blood tests adapted to the problem.
• Heart examination with ultrasound if the findings point to the heart.
• Endoscopy in case of suspicion of a foreign body or in case of long-term and unclear respiratory disease, with the possibility of taking samples from the respiratory tract.
• Stool sample with a separate method for lungworm if the medical history warrants it.

Coughing in dogs has many explanations, and most of them can be clarified quickly. If you are in doubt, you are welcome to contact us. If you have a video of a coughing fit, please bring it with you.