Coughing can be due to an extremely minor problem such as drinking water too fast, or it can be the first sign of serious problems of the lungs or heart.

The causes of dog coughs are many and varied, but most can be traced to some stimulation or irritation of sensory nerves in the throat, windpipe or smaller airways. The character of the cough may help to localize the problem to a specific area of the respiratory tree or cardiovascular system. The duration of the cough is an important part of the history, as well as vaccination and heartworm status, travel or boarding history, pre-existing health problems, medications, and any prior history of cough.

Coughs are triggered by irritants in the air passages and can be characterized as dry and hacking, moist and bubbly, gagging, wheezy, harsh or weak. It can be frequent, chronic, or intermittent and is often self-perpetuating as it dries the throat and leads to further irritation.

Dogs cough for a variety of reasons. Some common causes of coughing and gagging include foreign objects in the airway, bronchitis, bacterial pneumonia, heart disease, laryngeal paralysis, fungal infections, reflux esophagitis (similar to heartburn in people), food allergies, parasites, tumors, and other diseases. Environmental factors such as exposure to cigarette smoke, new perfumes, or new bedding or carpeting can also aggravate coughing. There could be some abnormality of the trachea, or possibly heart problems.

Some dogs will cough and gag whenever they drink water but never do it any other time. When dogs drink they actually throw the water toward the back of the throat with a neat trick of the tongue. If your dog drinks fast some water may contact the sensitive tissues within the larynx which triggers a cough response. If your dog can run, play, pant and breathe without a chronic cough and only does it when drinking, then it's nothing serious and you can ignore it.

For mild episodes, massaging your dog's throat may help lessen the symptoms.

Coughing may not sound like a serious problem, but sometimes it is a sign of a significant disease. Since there are so many possible causes of coughing in a dog, a veterinary check-up will help identify the cause. Many of the diseases associated with various types of coughing can be managed if they're caught early on. Coughing in Dogs

Some of the questions your veterinarian will ask you:

Kennel cough - Tracheobronchitis
High, dry coughs are typical of kennel cough. A dog with kennel cough appears to be healthy, but has frequent bouts of a hacking cough. Treatment includes isolation to avoid infection of other family or kennel dogs, temperature monitoring, rest, kennel cough syrup, or a children's over-the-counter cough syrup. A humidifier can help the dog breathe easier and thus reduce coughing and further throat inflammation. Cases usually heal in two weeks.

Kennel cough in puppies and toy breeds can be more serious because the throat irritation can be accompanied by thick secretions that can cause pneumonia.

Bordatella vaccine protects dogs from several strains of kennel cough. Any dog that is constantly exposed to other dogs away from home, such as boarding, dog training with other dogs, or dog parks should be protected against kennel cough.

Collapsed Trachea
Toy breeds of dogs are very prone to a genetic abnormality called tracheal collapse. The trachea is made up of cartilaginous rings in the shape of a C that are fibrous and soft on their innermost side. In collapsing trachea the inner soft portion of the windpipe is sucked into the airway during inspiration, partially occluding it. With time, the membranes lining the trachea become inflamed causing a chronic dry, hacking cough.

The condition is easily diagnosed by massaging the trachea near the dog's chest for a minute or two. Dogs with this problem go into a coughing spell as soon as you finish the massage. When the problem flares up, dogs are given a cough suppressant and an anti-inflammatory drug such as prednisone until the problem resolves. Air humidifiers are also helpful. These dogs do well wearing a harness rather than collars, and limited exercise until the cough is better. Various surgical techniques are used to attempt to cure this condition with mixed success.

Heartworm Disease
Heartworms are transmitted to dogs and cats by mosquitoes. Certain types of mosquitoes carry the heartworm disease, will bite a dog and ingest microscopic heartworm larva or microfilaria that lodge in the upper right side of the heart. Prevent mosquitoes from biting your dog. Depending on the number of heartworms present and the length of time they are there, the heart is slowly damaged and enlarges.

The presence of heartworms also causes inflammatory changes in the lungs. In dogs, these changes, along with pressure from the enlarged heart on the windpipe cause a dry to moderately moist cough. By the time a cough is present the disease is quite advanced and some of the changes to the heart and lungs are irreversible.

Dogs with heartworm coughs are noticeably ill. They are thin and their fur is dry and musty. They have a worn-out look about them and are often prematurely grey around their muzzle and toes. They are usually pot bellied due to an enlarged liver and excess fluid in their abdomens and are positive on a heartworm antigen test. The cough is worse when the dog is resting. The pet's history includes the fact that they are not receiving a heartworm preventative.

After assessing the degree of damage to the body, veterinarians prescribe medication. Coughs can take up to six months to resolve.

Worms
Canine hookworms and roundworms can also cause a cough, which is called a verminous cough. This problem is primarily a concern when a dog accidentally eats a hookworm or roundworm larva or egg, the larva burrows through pet's stomach or intestine into the blood stream.

When it reaches the lungs it is coughed up, re-swallowed and then matures in the pet's intestine. If a dog becomes infested with large numbers of larva due to an unsanitary environment the owner will notice the cough. Dewormers for Round/Hook/Tapeworms are commonly used to treat an infected dog. Preventing verminous coughs is a matter of sanitation. Dog feces need to be collected and disposed of properly.

Reverse Sneezing
Reverse sneezing is a forceful bizarre noise that sounds like the honking noise a goose makes. The dog makes a lot of noise and his sneeze sounds a little like a cough and a sneeze. Reverse sneeze syndrome is characterized by a series of rapid, loud, forced inhalations through the nostrils, lasting anywhere from 10 seconds to 2 minutes. Attacks occur on a sporadic, unpredictable basis.

Affected dogs appear completely normal before and after the attack. There is no loss of consciousness or collapse, though some times the appearance of the dog and the noise is upsetting to owners. You might think he has something caught in his nose. Many dogs have these attacks throughout their lives.

The exact cause of reverse sneezing is unknown, but the condition is usually not serious. However, it may be associated with sinusitis, incomplete closure of naso-pharynx, and other upper respiratory disorders.

Treatment is not necessary when episodes occur infrequently or on a random basis. To help your dog you may wish to try any of the following ideas: holding off both nostrils so the dog takes a breath through the mouth, or massaging the throat. These techniques are designed to stimulate a swallow reflex, which will help to stop the episode. You should notify the doctor if the severity or frequency of reverse sneezing changes, a nasal discharge or cough develops, or the general health of your pet changes.