Ask a Dog Vet and Get Answers to Your Dog Veterinary Questions
Can you describe the cough? Is it productive, wet, dry, hacking, etc?
There are many different types of cough and they have different causes. A dry hacking cough goes honk cough for example can indicate a condition called tracheal collapse. This type of coughing is more common when there is excitement. Productive cough is consistent with pneumonia. A description of the cough can be helpful in determining the ultimate cause.
Is the clear liquid at the end of a coughing fit? If so this is called a terminal retch and happens when there is a coughing fit that triggers a small amount of reflux from the esophagus or stomach. If there is no exposure to situations where he may have picked up a bug from other dogs such as trips to the groomers, daycare, vet visits, etc this is not likely to be a contagious cough.
A common condition of small dogs is a collapsing trachea and it is progressive which means that it can be noted in older dogs that have no history of coughing as younger dogs. This occurs because the rings of cartilage that keep the trachea open become weak with time and collapse, narrowing the airway and resulting in respiratory difficulty. This is exasperated when there is excitement or activity that requires the dog to move more air into and out of the lungs to maintain normal oxygenation.
This condition is usually managed medical with the assistance of cough suppressants, sedatives, using a harness instead of a color while on leash and sometimes antibiotics and steroids to treat secondary infections that may make coughing worse. Because this is a progressive disease, medical management will eventually fail and then the only option is surgery or placement of a tracheal stent to keep the airway open.