Coughing is a common protective reflex that clears secretions or foreign matter from the throat (pharynx), voice box (larynx), windpipe (trachea) or airways, and protects the lungs against aspiration. It affects the respiratory system by hindering the ability to breathe properly.
What causes a cough?
Common causes include obstruction in the windpipe, bronchitis, pneumonia, heartworm disease, lung tumors, kennel cough and heart failure.
Several tests can help determine the cause of the cough. Your dog should have a physical examination, including listening to your dog with a stethoscope, x-rays of the chest, and blood work as a starting base.
The treatment is dependent on the underlying cause. If the cause is an infection, the treatment is antibiotics. If the cause of coughing is heart failure, there are medications that can be given to help treat the heart condition.
If your dog is not eating, losing weight, and coughing significantly (more than just a cough here and there - maybe one small cough a week or so), then it is time to worry. Please, please see your veterinarian. I want the best for your dog.