Dogs lick the air for reasons ranging from completely harmless (they smell something interesting) to medically significant (nausea, dental pain, or seizure activity). A single brief episode is rarely a concern, but if your dog is doing it repeatedly or can’t seem to stop, something physical or behavioral is usually driving it.
Normal Scent Processing
Dogs have a specialized sensory organ called the vomeronasal organ, a cluster of sensory cells located in the roof of the mouth behind the front teeth. When your dog encounters an unusual or particularly interesting scent, they may lick the air, smack their lips, or chatter their teeth to push scent molecules toward this organ. It’s the canine version of a behavior called the flehmen response, which many mammals use to analyze pheromones and other chemical signals. The information gathered this way can tell a dog whether nearby animals are stressed, calm, or in heat.
This type of air licking is brief, situational, and easy to interrupt. Your dog catches a whiff of something, licks a few times, and moves on. If that describes what you’re seeing, there’s nothing wrong.
Stomach and Digestive Problems
This is one of the most common medical causes, and it’s frequently overlooked. A Canadian study examined 19 dogs with excessive licking behavior and found underlying gastrointestinal abnormalities in 14 of them. A separate study looked at 7 dogs with “fly biting” behavior (snapping or licking at the air as if catching invisible flies) and found digestive disease in 5.
The connection works similarly to a condition seen in human infants called Sandifer Syndrome, where acid reflux triggers unusual repetitive movements. Researchers believe the same mechanism applies in dogs: discomfort in the esophagus or upper digestive tract triggers a reflexive licking response, likely mediated by the vagus nerve. Acid reflux, delayed stomach emptying, inflammatory bowel conditions, and esophagitis can all be culprits.
Dogs with a stomach-related cause often lick the air, lick surfaces like floors or walls, swallow repeatedly, or lip-smack right before vomiting. If you notice any of these patterns, the air licking is worth investigating. In the studies mentioned above, treating the underlying digestive issue with dietary changes and acid-reducing medications resolved the licking behavior.
Something Stuck in the Mouth
Just like you’d use your tongue to work a popcorn kernel loose, dogs lick and tongue at foreign objects caught in their teeth or pressed against the roof of their mouth. This can look exactly like air licking. Veterinarians have found sticks wedged across the palate, chunks of food stuck between teeth, and even small tumors on the gums that triggered persistent licking.
Other signs of an oral problem include bad breath, excessive drooling, difficulty picking up food, and pawing at the face. A loose or painful tooth can also change how your dog moves their jaw, producing what looks like air licking when they’re actually trying to shift the tooth or dull the pain. Some foreign objects are lodged so firmly that sedation is needed to remove them.
Anxiety and Stress
Air licking sits on a spectrum. On one end, a quick lick can signal excitement or appeasement, a normal part of dog communication. On the other end, frequent or prolonged air licking can indicate anxiety. Dogs use repetitive oral behaviors as a self-soothing mechanism when they’re stressed, fearful, or overwhelmed.
Context matters here. If the licking happens during thunderstorms, when guests arrive, during car rides, or when your dog is left alone, anxiety is a likely driver. You’ll often see it paired with other stress signals like panting, yawning, pacing, or tucked body posture.
Compulsive Behavior
When air licking becomes so persistent that it disrupts your dog’s normal routines, it may cross into compulsive territory. Compulsive disorders in dogs develop when normal behaviors get stuck on repeat, much like compulsive hand-washing in humans. The key diagnostic sign: if your dog cannot be distracted from the licking, or returns to it within minutes of being redirected, the behavior may be compulsive.
Certain breeds carry a genetic predisposition. Dobermans, Labrador Retrievers, Golden Retrievers, Great Danes, and German Shepherds are more prone to compulsive licking behaviors. In Dobermans specifically, researchers identified a gene involved in brain development and the formation of receptors for an excitatory brain chemical. Up to 70% of a single Doberman litter can be affected by related compulsive behaviors like flank sucking. Dachshunds and Weimaraners also show elevated risk.
Compulsive licking is treated with a combination of behavioral modification and, in some cases, medication that affects brain chemistry. Treatment focuses on reducing stress, increasing mental stimulation, and breaking the cycle of repetition.
Focal Seizures
This is the cause that surprises most owners. A focal seizure is a burst of abnormal electrical activity confined to one area of the brain, and it can look nothing like the full-body convulsions people picture when they hear “seizure.” In dogs, focal seizures sometimes produce repetitive air licking, snapping at invisible flies, or brief episodes of staring and lip-smacking. Your dog may seem fully conscious during these episodes but unable to stop.
Focal seizures are typically a diagnosis of exclusion, meaning your vet will first rule out digestive problems, dental issues, and behavioral causes. The only way to definitively confirm seizure activity is through an electroencephalogram, which measures electrical activity in the brain. Because GI disturbances can mimic or even trigger fly-biting episodes, testing the digestive system is often part of the workup.
Cognitive Decline in Older Dogs
In senior dogs, new-onset air licking can be a sign of cognitive dysfunction syndrome, the canine equivalent of Alzheimer’s disease. As the brain deteriorates, dogs may develop repetitive behaviors that serve no apparent purpose. Air licking in this context usually appears alongside other changes: disorientation, altered sleep patterns, loss of house training, decreased interest in interaction, or staring blankly at walls.
If your older dog has recently started licking the air and you’re also noticing any of these other shifts, cognitive decline is worth discussing with your vet.
How to Tell What’s Causing It
The single most important factor is whether the behavior is a one-off or a pattern. A brief episode of air licking after your dog sniffs something new in the yard is normal sensory behavior. Repeated episodes, licking that lasts more than a few seconds at a time, or licking your dog can’t be snapped out of all warrant a closer look.
Start by checking your dog’s mouth. Look for anything stuck between the teeth, pressed against the gums, or lodged on the roof of the mouth. Check for redness, swelling, broken teeth, or unusual growths. If the mouth looks clear, pay attention to timing. Does the licking happen around meals, after eating, or alongside other signs of nausea like drooling, grass-eating, or gulping? That points toward a digestive issue. Does it happen in stressful situations? That suggests anxiety. Does it seem random, brief, and trance-like? Focal seizures or compulsive behavior become more likely.
Because digestive disease is so commonly found behind this behavior, many vets will start the diagnostic process there, especially if switching to a bland or hypoallergenic diet and reducing stomach acid leads to improvement. If the licking persists after GI causes are addressed, the investigation moves on to neurological and behavioral explanations.