Your dog's health issue would be best addressed by a veterinarian performing a thorough health exam. There are many reasons why a dog will cough (respiratory infection, allergies, tracheal collapse, lodged foreign body to name just a few). Call and schedule an appointment for your dog...Drs. McKinnon and Barker-Olson are very good, caring veterinarians who'll give your fur baby the attention they need and deserve. In the meantime, keep a journal of when your dog begins these coughing spells, what he/she was doing right before the coughing began, and what if anything seems to relieve the cough (ex- drinking or eating, laying down and resting...), how long the coughing persisted, when you first noticed the problem, and any changes you have made in your dog's food or home environment prior to the coughing beginning.
Unfortunately that's a hard question to answer. Without an examination to be able to evaluate the heart and trachea and listen to the lungs, there is not much to recommend.
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