While some coughing is normal in dogs, especially if it can be attributed to eating or drinking too quickly, excessive coughing and hacking with no obvious reason can be a sign of a  potential problem. Several conditions can cause your dog to cough and/or hack:

If your dog has been boarded lately or somehow come in contact with a large number of dogs, and he has developed a deep, hacking cough that gets worse with exertion, then your dog may have kennel cough. Caused by a highly contagious virus, kennel cough is associated with severe coughing and inflammation. Any age or breed of dog can become sick with bordetella. There is an effective vaccination that can be given by your veterinarian.  

Listen to the sound of your dog’s cough. If your older or overweight dog develops a cough that sounds more like a honking sound, it is possible your dog is experiencing a collapsed trachea. Other signs you may notice are gagging while eating or drinking, low tolerance for activity, and episodes of respiratory distress. In addition to elderly and overweight dogs, small breed dogs have a higher incidence of tracheal collapse. 

Dogs do not normally show signs of a common cold the way humans do; if you notice your dog exhibiting lethargy, a yellow, mucous discharge from her eyes and nose, and a dry cough, it is possible your dog is experiencing canine distemper. If your dog has been vaccinated for distemper, this disease is less likely.  

Congestive heart failure can occur when the heart becomes enlarged and obstructs airways, thus producing a cough and/or gagging episodes in your dog. Heartworms can also cause a dog to cough excessively. Pericardial effusion is the buildup of fluid around the heart and can  cause your dog to produce a “wet” cough or a gagging sound. Be sure to notice if this cough occurs mostly at night or when your dog is lying down as this can be a sign of fluid gathering in the lungs. Great Danes, Cavalier King Charles Spaniels, and older dogs are more at risk for heart disease.  

Do you live on or near a farm? Do you have chickens or live near chickens? Has your dog developed a “wet” cough that almost sounds like a gargling sound? Then it is possible your dog could have inhaled some fungal spores or animal droppings and is now coughing as a result. Dogs can also inhale fungal spores after spending time in damp areas. Fungal infections can lead to pneumonia, so if you suspect this is the problem, get your dog to the veterinarian immediately. 

Always be sure that your dog has not swallowed a foreign object that might be stuck in his throat. A foreign object does not have to choke the dog, but can be a huge irritation. Allergies can make your pup as miserable as they make humans. Pollen, mold, household dust, and insect mites can have much the same effect as they have on humans. If allergies are what is plaguing your pooch, you might also notice itchiness in him. Although it is very rare, dogs can develop tuberculosis. You may notice a “wet,” productive cough accompanied by bloody phlegm. Coccidiosis is another disease that is characterized by a wet, productive cough. Because these signs can signal both mild and more serious diseases, it is imperative that your veterinarian diagnose the cause of the cough. Any age or breed of dog can suffer from allergies, tuberculosis, coccidiosis, or other auto-immune illnesses.

Because the disease that is causing the coughing or hacking in your dog could be serious, it is best to see a veterinarian so that he can do a physical exam and lab testing if needed to confirm a diagnosis. Kennel cough is generally mild in otherwise healthy dogs; however, if your dog is very young or a toy breed, untreated kennel cough can lead to pneumonia, and should be treated by a veterinarian. The characteristic goose honk of tracheal collapse must be professionally treated. Medication is most likely necessary, and surgery may be a possibility as well. Distemper is usually prevalent in dogs who have not been vaccinated; distemper can develop in dogs who are in the process of receiving all their shots (when immunity from the pup’s mom is decreasing, and vaccines have not provided full immunization just yet). Distemper can be fatal, especially in younger dogs. Heart disease is highly serious; however, if it is caught early, the prognosis can be positive. Any suspicion of heart disease should be treated by your veterinarian. Fungal diseases can lead to pneumonia, so they should be diagnosed and treated by a veterinarian, as should any persistent cough.

Always keep your dog’s vaccinations up to date, as they protect against canine distemper and the bordetella virus that leads to kennel cough. Do not kennel your dog in dirty cages, old chicken coops, or near pigeons as they might inhale the bird droppings and develop a fungal infection. Maintain your dog’s chew toys; once they start to get worn, throw them out so your dog won’t accidentally swallow part of a toy.

Treating coughing and hacking in your dog can range from less than $100 to $2,500; kennel cough generally costs $100-300 to treat. Curious about which health plan is right for your dog? Head over to Forbes' breakdown of pet insurance providers.