Third, a persistent cough can be caused by an underlying heart condition such as a heart-based tumor or a pulmonary edema caused by heart failure. Heart conditions may cause coughing because heart conditions can trigger fluid accumulation in the lungs. A cough caused by a heart condition will typically be a wet-sounding cough and will be accompanied by exercise intolerance.

Fourth, a cough can be a symptom that your dog has parasites. Two of the most common parasites to cause coughing are roundworm and heartworm. Roundworms usually make their home in your dog’s intestines. Sometimes, however, the roundworms travel into your dog’s lungs. Once in the lungs, the roundworms will migrate up the windpipe and be coughed up. To learn more about roundworm prevention, signs and treatment click here. Heartworm is a potentially fatal disease in which parasitic worms make a home and grow in your dog’s heart. The cough associated with heartworm often occurs when the disease has progressed unchecked for a long enough time for the heartworm parasites to prevent the transmission of oxygen-rich blood from between the lungs and the heart. A dog who is coughing to due to heartworm will be very weak and even walking or the slightest exercise will cause coughing. To learn more about heartworm prevention, signs and treatment click here.