The short answer
The most common cause of a dog coughing and then gagging is kennel cough, an airway infection picked up from other dogs. Other causes include a collapsing windpipe in small breeds, something stuck in the throat, heart disease in older dogs, and nausea. A dog that is bright and eating can usually see a vet within a day or two. A dog that is choking, struggling to breathe or has pale, blue or grey gums needs an emergency vet now.
Call a vet now if your dog has
- Choking: pawing at the mouth, panic, unable to breathe or make normal sounds
- Struggling to breathe, or breathing fast and hard at rest
- Blue, grey or very pale gums or tongue
- Collapse or fainting during a coughing fit
- Unproductive retching with a swollen belly, which can be bloat
- Coughing up blood
A coughing fit that ends in a dramatic gag (often with a little white foam) is one of the most common reasons owners call the vet. It looks and sounds as though your dog is choking or about to vomit, and it is easy to mistake one for the other.
Most of the time the cause is an irritated airway rather than anything stuck, and the dog is otherwise well. But a handful of causes are urgent, so it is worth knowing how to tell them apart.
First: is your dog choking?
If your dog is pawing at its mouth, panicking, drooling, unable to breathe or making no sound, or if the gums are turning blue or grey, treat it as choking. Look in the mouth only if it is safe (a frightened dog may bite) and remove an object only if you can see it clearly and grasp it easily, without pushing it further back. Then get to a vet immediately, even if the object comes out, because the throat may be injured.
If your dog is coughing and gagging but can breathe, is pink-gummed and settles between fits, it is not choking, and you have time to work out what is going on.
Coughing, gagging and reverse sneezing look alike
- A cough forces air out of the lungs, often in fits. Many dogs follow a coughing fit with a gag or retch.
- Gagging is a reflex at the back of the throat that can follow a cough, or come before vomiting when a dog feels nauseous.
- Reverse sneezing pulls air in through the nose in loud, rapid snorts, usually with the neck stretched forward. It is caused by irritation at the back of the nose and soft palate, is usually harmless, and stops on its own within a minute or so.
The order can be a clue. If your dog coughs first and then gags, the problem is more likely in the windpipe, lungs or, sometimes, the heart. If your dog gags first and then coughs, the throat or larynx (voice box) is more likely involved.
A 30-second video of an episode is the single most helpful thing you can take to the vet.
Common causes of coughing and gagging
Kennel cough. By far the most common cause in an otherwise healthy dog, especially a few days after kennels, daycare or a dog park. It causes a sudden, harsh, honking cough that often ends with a gag and a little foam. Most dogs stay bright and recover in one to three weeks. See kennel cough symptoms.
Collapsing trachea. In some dogs (especially toy and small breeds such as Yorkshire Terriers, Pomeranians, Chihuahuas and Shih Tzus) the cartilage rings that hold the windpipe open weaken and flatten. The result is a dry, honking, goose-like cough that comes on with excitement, pulling on a collar, eating or drinking, and is often long-standing. Weight control, a harness instead of a collar and medicines help many dogs.
Something stuck in the throat or airway. Grass seeds, bits of stick, bone fragments and pieces of toys can lodge in the throat, causing sudden, persistent gagging and coughing. This needs a vet promptly.
Heart disease. An enlarged heart can press on the airways, and heart failure causes fluid to build up in the lungs. A cough that is worse at night or at rest, especially in an older small-breed dog with a heart murmur, together with faster breathing at rest, should be checked soon. See why is my dog breathing fast.
Pneumonia and bronchitis. Lung infections cause a softer, wetter cough, often with lethargy, fever and poor appetite. Chronic bronchitis causes a cough that lasts for months.
Laryngeal paralysis. Mainly in older large dogs such as Labradors, the voice box does not open properly, causing loud, raspy breathing, a changed bark and gagging, which get worse in heat and with exercise.
Nausea. A dog that gags without coughing, licks its lips and drools may be about to vomit. See dog throwing up white foam. Repeated unproductive retching with a swollen belly can be bloat, an emergency.
Parasites. Lungworm and, in areas where it occurs, heartworm can cause coughing. Routine parasite prevention helps.
When to see a vet
| What you notice | What to do |
|---|---|
| Occasional cough-and-gag, dog bright and eating | Call your vet for advice. Book a check if it continues |
| Honking cough after mixing with other dogs | See a vet within a day or two. Keep away from other dogs |
| Cough lasting more than a week, or getting worse | Book a vet visit |
| Cough with lethargy, fever, poor appetite or fast breathing | See a vet today |
| Cough at night or rest in an older dog with a murmur | See a vet soon |
| Choking, struggling to breathe, blue or pale gums | Emergency vet now |
What you can do at home
While you wait to see the vet, for a dog that is breathing comfortably between fits:
- Swap the collar for a harness to take pressure off the windpipe.
- Keep things calm: short, gentle walks and no rough play.
- Keep the air clean: no smoking, scented sprays or dusty jobs near your dog.
- Keep your dog away from other dogs in case it is kennel cough.
- Do not give human cough medicines, which can contain ingredients that are toxic to dogs.
If a fit does not stop
Most coughing fits settle within a minute or two. If your dog cannot stop coughing, becomes distressed, collapses, or the gums change colour, go to the nearest emergency vet.
What the vet will do
The vet will listen to the heart and lungs, feel the throat and windpipe, look in the mouth, and ask when and how the cough happens. Gently pressing on the windpipe often triggers a cough in dogs with kennel cough or tracheal collapse. Depending on what they find, they may recommend chest X-rays, blood tests, heart scans or, for a stubborn cough, an airway camera examination. Treatment depends on the cause, from rest and time for kennel cough, to medicines for heart disease or a collapsing trachea, to removing a foreign object.
For more on breathing problems, see our breathing and cough section.
Common questions
Why does my dog cough like something is stuck in its throat?
This is the classic description of kennel cough, whose harsh, hacking cough often ends in a gag. It can also be a genuine object caught in the throat, a collapsing windpipe, or irritation at the back of the throat. If your dog is distressed, pawing at its mouth or struggling to breathe, treat it as choking and get help immediately.
Is reverse sneezing the same as coughing?
No. Reverse sneezing is a series of loud, snorting breaths pulled in through the nose, usually with the neck stretched out, and it typically stops on its own within a minute. It comes from irritation at the back of the nose and is generally harmless. A cough pushes air out and often ends in a gag.
Why does my dog cough and gag at night?
Coughing that is worse at night or when lying down can be a sign of heart disease, particularly in older small-breed dogs with a heart murmur, because fluid can build up in the lungs. It can also happen with airway problems and kennel cough. Count your dog’s resting breathing rate and book a vet visit.
Can allergies make a dog cough and gag?
Allergies and airway irritants such as smoke, dust and strong sprays can cause coughing in some dogs, and chronic bronchitis causes a long-lasting cough in others. Because many more serious conditions look similar, a cough that lasts more than a couple of weeks should be checked by a vet.
Sources
- What Causes Gagging in Dogs, and Why Do Dogs Gag?, American Kennel Club
- Tracheal collapse, Cornell Richard P. Riney Canine Health Center
- Reverse Sneeze in Dogs, VCA Animal Hospitals
- Tracheal Collapse in Dogs, Merck Veterinary Manual
This article is general information to help you decide what to do next. It is not a diagnosis and is not a substitute for examination by a veterinarian. If you are worried about your dog, call your vet.
Reviewed by Winzah, Editor, on . How we research and check articles.
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