Why Do Dogs Sneeze?

It’s common for dogs to sneeze and it’s generally nothing to worry about. Much like humans, dogs sneeze because their nasal passages get irritated, although the irritants are often different. Many dogs can also sneeze when playing. Unlike humans, dogs rarely sneeze due to colds or allergic reactions. Colds are more likely to induce coughing and allergies in dogs tend to show up as skin irritation. Understanding the causes of sneezing can help dog owners keep their dogs healthy and get them to the vet when necessary.

What is a Sneeze?

Sneezing is an involuntary contraction that forces air out of the nose. It is a tactic the body uses to stay healthy. The force of the air can expel particles in the nasal passage, which is helpful when those particles are irritants. In dogs, a snort is very similar to a sneeze, except that it is voluntary. A snort is also used to expel foreign objects in the nose, the only difference is that the dog is consciously taking action to cause a snort.

Sneezing to Communicate

Interestingly, not all sneezes in dogs are a reaction to irritated nasal membranes. Many dogs sneeze when playing to communicate with other dogs. Owners of small dogs may see this more regularly than those with larger dogs. In these cases, the sneeze is a calming signal. It is most often seen during rambunctious play or plays fighting. It signals to the other dog that they are just playing and there is no need to get aggressive. Some dogs also sneeze as a way to encourage play or seek attention.

Foreign Bodies

Dogs may sneeze due to having something in their nose that should not be there. Hunting dogs that use their noses to follow trails are especially prone to this, as are dogs that enjoy digging in the dirt. Foreign bodies can include soil, grass, and sometimes bugs. In U.S. states west of the Mississippi, foxtails are a common culprit. The heads of these plants turn dry and brown in summer and they have spikes that allow them to burrow into the soil. They can get into many parts of a dog’s body, including the nose.

Nasal Infection

Although respiratory infections are more likely to cause coughing in dogs, some owners do observe sneezing. One type of infection, caused by the Aspergillus fungus, does induce sneezing in dogs. This fungus is found outdoors in dust, hay, and grass clippings and is introduced to the dog’s nose when they sniff these items. The infection can also cause pain, bleeding or discharge from the nose, and visible swelling.

Nasal Mites

Dogs are also prone to nasal mites, also known by the scientific name Pneumonyssoides caninum. The most common way for a dog to be infected by nasal mites is by digging in the dirt with their face or touching the nose of an infected dog. The microscopic bugs infect the nose and sinuses of the dog, causing itching and fits of sneezing. They can also trigger nose bleeds and nasal discharge. The infection can be identified by looking at a nasal swab under a microscope.

Infected Tooth

On occasion, an infected tooth can cause sneezing. This happens because some of the upper teeth have roots that are very close to nasal passages. When a tooth infection causes swelling at the root, this irritates the nose, triggering sneezes. Other signs of a tooth infection include bad breath, swollen or bleeding gums, swelling of the face, excessive drooling, and signs of tenderness or pain.

Tumors

Although other causes of sneezing are more likely, nasal tumors are not uncommon in dogs. Collies and other breeds with longer noses are especially susceptible. As the tumor is in the nasal passage, it causes a blockage that the body tries to expel through sneezing. Tumors also cause chronic nasal discharge. Cancer in dogs is often caused by second and third-hand tobacco smoke. Although it is rare for these types of tumors to metastasize, they can spread locally and destroy the structure of the nose.

Sensitive Noses

In many instances, sneezing is caused by a dog’s sensitive nose. A dog’s sense of smell is estimated to be at least 10,000 times more sensitive than that of a human. This means that smells that don’t bother humans can be very pungent for dogs. Household products like cleaners and deodorants can irritate dogs, as can cigarette smoke. Their noses are also sensitive to dust and they can often sneeze when vacuuming moves dust around.

Brachycephalic Breeds

Obstruction of the upper airways can also cause sneezing and this is especially common in dog breeds known as brachycephalic. These dogs have compressed nasal passages and are more prone to sneezing than other dog breeds. The sneezing allows them to clear fluid and debris from their shortened noses. Brachycephalic breeds are those with pushed-in faces and short muzzles. They include pugs, Boston terriers, and bulldogs.

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When to See a Vet

Generally sneezing is perfectly normal, but occasionally it can be a sign that something is wrong with a dog. If a dog cannot stop sneezing or is sneezing in a different pattern, you may have to consult a vet. Symptoms that accompany sneezing can also point to a bigger problem. Owners should look for bleeding or excessive discharge when sneezing, the dog pawing at their nose, coughing, lethargy, or loss of appetite. The treatment the vet recommends will depend on the cause of the sneezing.