Dog Coughing for Days: Kennel Cough and Other Causes

Coughing is a reflex that helps a dog clear irritants from its airways. An occasional cough is usually nothing to worry about, but a cough that lasts for days deserves attention. Knowing the common causes helps you describe the problem accurately to your veterinarian and care for your dog while you wait.

What is kennel cough?

"Kennel cough" is the common name for a group of contagious tracheobronchitis infections caused by several bacteria and viruses, most often the bacterium Bordetella bronchiseptica and canine parainfluenza virus. It spreads through the air and shared items, so it's common where many dogs gather, such as boarding facilities, parks, grooming salons and shelters.

• Type of cough: a loud, dry, honking cough, or one that sounds like the dog is choking, often ending with a gag as if about to vomit.
• Usually appears: a few days after contact with other dogs.
• Worse: when the dog pulls on the leash, gets excited, exercises or drinks.
• Most cases are mild: the dog keeps eating and playing normally and recovers on its own in about one to three weeks.
• Can become serious: in puppies, senior dogs and dogs with underlying illness, it may progress to pneumonia.

Vaccines are available that help reduce the risk and severity. Ask your veterinarian whether your dog should have one, especially if it's often boarded or plays with other dogs. Your vet decides the exact schedule.

Other causes of coughing

• Collapsing trachea: common in small breeds from middle age onward. A honking cough that worsens with collar pressure, excitement or obesity. Using a harness instead of a collar reduces pressure on the neck.
• Heart disease: older dogs, especially those with a heart murmur, may cough more at night or at rest, with fast breathing and tiring quickly on walks.
• Heartworm: spread by mosquitoes. Early on there are few signs; later a persistent cough, fatigue and weight loss. See our related article on heartworm.
• Foreign bodies, grass or grass seeds: sudden coughing or gagging after running through grass, eating bones or chewing sticks.
• Pneumonia: a moist, productive cough with fever, rapid breathing and loss of appetite.
• Environmental irritants: cigarette smoke, cooking smoke, dust, air fresheners.
• Distemper: in unvaccinated dogs it may start with a cough, runny nose and eye discharge, then worsen.

Home care while you monitor

If your dog has a mild cough, is still eating and playing normally, and your veterinarian has advised monitoring at home, you can:

• Isolate: keep your dog away from places with many dogs and from group play for as long as your vet advises. Kennel cough spreads easily.
• Use a harness instead of a collar: so nothing presses on the windpipe.
• Limit strenuous exercise: gentle walks, no running or overexcitement.
• Keep the air clean: no smoking indoors, avoid cooking smoke and limit chemical sprays.
• Maintain moderate humidity: very dry air can make coughing worse.
• Wash bowls separately and launder bedding often.
• Don't give human cough medicine: many contain ingredients unsafe for dogs. Use any medicine only as directed by your veterinarian.

When to see a vet

Take your dog to the vet if the cough lasts more than a few days, or sooner if you see any of the following:

• Rapid, labored or open-mouth breathing at rest.
• Blue or very pale tongue or gums: this is an emergency.
• Coughing up blood or phlegm, with fever.
• Loss of appetite, lethargy, thick nasal discharge or eye discharge.
• A puppy, senior dog, or dog with heart or respiratory disease that is coughing.
• A sudden, violent cough after eating a bone, chewing a stick or running through grass.
• Coughing mostly at night, with quick tiring or a gradually swelling belly.
• A cough that returns every time your dog gets excited or pulls on the leash.