Cough in dogs is absolutely one of the most common things that critical care veterinarians see.
"When we think about cough in dogs, that is absolutely one of the most common things that we see," says Liz Rozanski, DVM, associate professor of emergency and critical care at the Cummings School of Veterinary Medicine at Tufts University. "And just the same as a cough for a person, the question is, is the cough infectious? Could they have been exposed to another dog and have kennel cough or Bordetella infection? Could they have something like tracheal disease or lower airway disease where they're having kind of the chronic bronchitis that people get?
Dogs don't really get asthma like people, and that is because asthma is defined as bronchoconstriction where the airway is actually narrow and dogs don't do that, they don't have asthma. Cats do, horses do, but dogs don't. But they absolutely get chronic bronchitis — a chronic inflammatory disease particularly in small-breed dogs. Other causes of cough that we think about are scary things like a lung tumor, which can sometimes cause cough. Heart disease can sometimes cause cough. Pleural effusion or fluid in the outside of the lung cavity can cause cough. So, what we recommend is look at the dog, talk to the people—have they been exposed to other dogs, did a puppy come over, do they just go to the groomer, how long has the cough been going on for? Sometimes people overlook cough a little bit, the dog's been coughing really for 5 years and it didn't really bother them, but now it's finally bothering them.
So, what's been going on from a diagnostic standpoint? Certainly, a chest X-ray—we're going to absolutely start with the chest X-ray—heartworm test is reasonable particularly if you live in a heartworm area, looking for evidence of anything you can treat more specifically, and then based on what you find we look at primarily trying to control infection if there's any infection there. Sometimes we look at suppressing the cough, as well. And the rationale for that is a) it makes the dog more comfortable, also more comfortable for the owners, but importantly the more coughing the dog does, the more airway inflammation there is and then the more confidence there is. It's really a very vicious cycle, so if we can try to break that cough cycle for a couple of days, we'll get the dogs to feel a lot better with that. So, kind of our summary of what do you do for cough is good history, good physical exam— kind of the tenants of veterinary medicine—chest X-ray, and then decide. Sometimes we'll look down in their airways with a bronchoscope, sometimes we'll use fluoroscopy, sometimes we'll do a CT scan, so there's lots of things we could do, but the basics, good history, physical exam, and a chest X-ray."