My dog keeps dry hacking. What's causing it and what should I do?

Hi and thanks for using Petco Pet Education Center, formerly Petcoach! Sorry to hear about Cody. Dry hacking/coughing can be caused by many things and it's hard to answer this without being able to ask you questions since the history is very important when trying to figure out why something is happening. Like if you said he was boarded, groomed, went to doggie daycare, was around strange dogs recently, I would then be thinking about kennel cough. Coughing has many causes including kennel cough, infection, inflammation, allergies, heartworm disease, parasites, laryngitis, bronchitis, irritation from a foreign body or something he ate, irritants in the air, toxin exposure, among many other causes. I always suggest that if something is wrong and it persists, worsens, or other signs develop, always have your pet checked out immediately by your veterinarian. They can get a good history, perform a physical exam, and then advise you on diagnostics/treatment. Possible tests could include fecal/blood/urine tests and x-rays of the chest and upper airway. Once a diagnosis is made or suspected, a sound treatment plan can be discussed and implemented. Good luck and I hope Cody recovers from this soon.