By Dr. Bob Encinosa
As with people, there are many reasons why dogs cough. Many times coughs are self- limiting, caused by viruses or irritants, for example, and go away on their own. Other causes of coughing can be much more dangerous. As veterinarians, we worry the most about things like heartworm disease, cancer, and congestive heart failure.
How do you know when a cough is worth a visit to the veterinarian? When a cough is persistent or seems to be getting worse, it’s worth a doctor’s look. Also when coughs are accompanied by fever, loss of appetite, or labored breathing, there’s sure to be something serious going on that deserves a closer look. Don’t delay. Respiratory issues can worsen quickly and 24 hours can make a big difference, sometimes life and death, especially with illnesses such as pneumonia and heart failure.
Whether or not a cough is “productive” is a very important thing to note when observing a cough. “Productive” means that the dog is trying to cough up material in the form of phlegm or other fluid from their lungs or airways. Rarely, when coughing this fluid up, will they actually spit it out for you to see. More often the cough is followed by a gag or wretch as they bring up the fluid. They will then swallow, allowing the fluid to be safely discarded through the intestinal tract. Productive coughs are often seen with pneumonia or severe bacterial infection and congestive heart failure.
Non- productive, or dry coughs, can sound more like a hacking or honking cough. This type of cough is often seen with various types of bronchitis, including kennel cough, and with the collapsing tracheal syndrome often seen in small breed dogs.
Another important observation that can be helpful in finding the cause of a cough is when does the cough occur? A cough that happens only after drinking water can mean very different possible causes than a cough that occurs only after exercise or after first waking in the morning. There are dozens and perhaps hundreds of causes of coughing in dogs. We, as veterinarians, need all the help we can get in figuring out the cause of the cough.
Persistent or severe coughs will often necessitate chest X-rays (radiographs), heartworm tests and other blood work to get to the answer. The good news is that most causes of coughing are very treatable. Even heartworm disease and congestive heart failure can be treated very effectively if diagnosed in time.