Kennel cough is a respiratory infection that affects dogs of all ages and is caused by a range of different viruses and bacteria that are inhaled by the dog into its respiratory tract. The most obvious symptom of kennel cough is a persistent, forceful cough that often sounds like a goose honk. This cough is usually dry and hacking, and can be followed by gagging or retching that sounds like the dog is trying to clear its throat. The cough can be hoarse or productive, in which case it can be followed by a gag, swallowing motion, or the production of mucus. It is distinct from a cough-like sound known as reverse sneezing, which is common in certain breeds and is triggered by irritation in the throat. Reverse sneezes can be normal in certain dogs and breeds, and usually only indicate the presence of post-nasal drip or a slight irritation of the throat.

Other symptoms of kennel cough can include fever, runny nose, eye discharge, sneezing, lowered appetite, lethargy, and watery eyes. In most cases, dogs with kennel cough will appear healthy apart from coughing. However, in some cases, usually in puppies or older dogs with compromised immune systems, kennel cough can lead to a more serious infection that manifests as pneumonia and secondary bacterial infections. Serious symptoms like high fever, loss of appetite, moist or productive cough, thick yellow or white nasal discharge, and disinterest in normal activities are signs of these severe cases.

If your dog has symptoms of kennel cough, it is important to follow up with your veterinarian. While kennel cough is not normally dangerous and is likely to need no treatment at all, serious, ongoing kennel cough infection can lead to pneumonia.