Why is my dog coughing and gagging?

Brief summary:

• Health problems that cause coughing include kennel cough, respiratory infections, heart disease, fungal infections, lungworm, heartworm and distemper
• If your dog’s cough is persistent, contact your vet
• If your dog coughs up white foam, treat this as an emergency
• Coughing up blood could be a sign of stomach trouble, or that your dog has eaten something poisonous

Kennel cough 

Kennel cough is the most likely cause of your dog’s cough. It’s usually a dry, hacking cough that sounds almost like your dog has something stuck in their throat. 

Kennel cough is highly contagious, dogs are most likely to get it when they’re around other dogs. If coughing is your dog’s only symptom — i.e. they’re in great health except for their persistent cough — then there’s a good chance they have kennel cough.

In most cases, kennel cough goes away on its own after 2-3 weeks. It’s also easy to prevent — ask your vet about the routine kennel cough vaccination.  

Read more: Kennel cough in dogs

Problems with the lungs or respiratory tract 

Just like humans, dogs can suffer from pneumonia and other infections of the airways — even dog flu (canine Influenza). Further symptoms may include laboured breathing, wheezing and gagging after coughing. 

Your vet will be able to diagnose and treat lung or respiratory infections easily, especially if they’re caught early on. 

A prolonged cough can also be a symptom of lung cancer, although this is rare.

Chronic bronchitis

Chronic bronchitis is a long-term condition often seen in older dogs. It leads to a persistent dry cough and requires long-term management.

Laryngitis

Laryngitis causes a harsh, dry cough that can become soft and moist over time. Other symptoms include noisy breathing and a change in your dog’s bark.

Heart disease 

Dogs can also suffer from heart problems and heart disease, which may cause coughing.

Thickened and weakened heart muscle can put pressure on a dog’s lungs and airways. Aside from coughing, symptoms of heart problems in dogs may include visible tiredness, shortness of breath, a change in their weight and even collapse. 

Your vet will recommend a course of action, which may include medication, a change in diet and added exercise.

Fungal infections

Dogs can develop fungal infections by coming into contact with yeast and other fungi in dirt, stagnant water, or through the air. Symptoms include a cough and a high fever. Your vet can prescribe medication to treat the infection.

Lungworm

Lungworm in dogs is a parasitic worm that can be serious, even fatal, if untreated. Dogs usually contract it after eating slugs and snails, so take care to prevent this when out walking. The worm lives in the host’s heart and blood vessels. Other symptoms include reluctance to exercise, weight loss, bleeding, and difficulty breathing. Treatment involves a special worming routine, prescribed by your vet. Regular worming will help to prevent lungworm​.

Heartworm

While heartworm isn't native to the UK, cases are on the rise here, mainly in dogs that have travelled or been imported from heartworm hotspots like southern and eastern Europe. This serious condition is spread by mosquitoes. Signs to look out for include coughing, weight loss, and tiredness. Treating heartworm usually involves monthly medication or a six-month injection. Just like lungworm, you can stop heartworm with regular worming treatments.

Distemper

Canine distemper is a serious and highly contagious virus that’s airborne, meaning it spreads through the air. Aside from coughing, symptoms include fever, lethargy, sickness and diarrhoea. 

Like other viral infections, it’s quick and easy to vaccinate against distemper - just be sure to keep your dog up to date with their booster vaccinations.

Frequently asked questions

My dog’s cough is persistent. What should I do?

Coughing can be a symptom of many different conditions. As an owner, the best action you can take is to keep an eye on your dog and to consult your vet if you’re concerned. They’ll be able to pinpoint exactly what's wrong, and then to advise you on the right treatment.

Why is my dog coughing up white foam?

Coughing up white foam can be a sign of Kennel Cough, bloat or gastrointestinal distress. The latter two conditions are classed as emergencies, so if your dog is coughing up white foam, contact your vet or emergency care provider right away.

Read more: Comprehensive dog vomit colour guide

Why is my dog coughing up blood?

Is the blood a normal, fresh shade of red or a darker red? Coughing up red blood can be a symptom of trouble with the stomach lining, or a reaction to a poisonous substance.

If the blood is dark red, this means it’s been in your dog’s system for a while. Coughing up dark red blood could be a sign of a stomach ulcer.

If your dog coughs or vomits blood repeatedly, contact your vet for more help and advice.

My dog coughs when they’re excited. Is that normal?

It’s perfectly normal for some dogs to cough when they’re excited or anxious, especially small breeds. This usually occurs simply because they’re breathing harder.

Intense coughing while excited or anxious may be a sign of tracheal collapse. If the coughing is excessive, or doesn’t settle down after your dog’s excitement is over, have a chat with your vet.

Why might my dog be gagging?

Gagging can sometimes accompany a cough and may be because of a totally separate issue or an extension of a respiratory problem. For example, kennel cough can cause both coughing and gagging. Another cause may be a foreign body in the throat, which can cause gagging as the dog tries to dislodge it. This requires immediate veterinary attention.

Respiratory infections such as bronchitis or pneumonia can also lead to gagging alongside symptoms like wheezing and laboured breathing. As mentioned above, tracheal collapse is a common cause of harsh coughing followed by gagging in small breeds, and is usually triggered when the dog is excited or pulling on a leash.

On top of this, conditions like laryngeal paralysis, where the larynx does not open properly, and advanced heart disease, causing fluid build-up in the lungs, can result in gagging. If your dog is gagging frequently, speak to your vet. They'll try to pinpoint the underlying cause and come up with an appropriate treatment plan. If gagging is accompanied by severe symptoms like difficulty breathing, vomiting, or collapse, seek emergency care immediately.

Need more info?

For more help and advice on your dog’s cough, have a chat with your local vet. Use our find a vet page to locate your nearest practice.