Why Do Anxious Dogs Lick Their Lips?

• Lip licking can be a subtle sign that a dog feels anxious, uncertain, frustrated, or socially uncomfortable.

• It is often considered a displacement behavior and may also help communicate peaceful or non-confrontational intentions.

• A single lip lick does not prove anxiety. Context and the dog's other body-language signals matter.

• Anxious lip licking may occur alongside yawning, looking away, pinned-back ears, panting, trembling, pacing, or a lowered body posture.

• If your dog repeatedly lip licks in a particular situation, increasing their distance from the trigger can help prevent anxiety from escalating.

• Frequent lip licking outside stressful situations can indicate nausea, dental pain, oral disease, or another medical problem.

• Sudden or persistent lip licking accompanied by vomiting, drooling, difficulty eating, retching, abdominal swelling, or obvious pain warrants veterinary attention.

When dogs become anxious, their nervous system shifts into a state designed to help them cope with potential danger.

We often think of the classic "fight or flight" response, but canine behavior is much more nuanced than that. Dogs may freeze, avoid eye contact, move away, seek reassurance, sniff the ground, scratch themselves, yawn, or lick their lips.

The MSD Veterinary Manual lists yawning and lip licking among displacement behaviors that may occur in dogs experiencing fear and anxiety. MSD Veterinary Manual: Behavior Problems of Dogs

A displacement behavior is essentially a normal behavior occurring at a moment when its usual purpose is not obvious.

Imagine being asked a difficult question during an uncomfortable meeting and suddenly finding yourself adjusting your glasses or fiddling with a pen. The pen is not the problem. The behavior gives the nervous system somewhere to channel that tension.

Lip licking may serve a similar purpose in dogs.

Importantly, scientists are still investigating exactly what these small behaviors mean. It would be too simplistic to say, "lip licking equals anxiety." Depending on the situation, the behavior may reflect stress, uncertainty, frustration, increased arousal, social communication, or a combination of these factors.

Possibly, and there is growing evidence supporting that interpretation.

Appeasement behaviors are signals thought to communicate something roughly equivalent to: "I don't want trouble."

A 2023 study involving 53 dogs examined several displacement behaviors while unfamiliar people approached the dogs in either neutral or mildly threatening ways. Nose licking, lip wiping, and blinking were particularly associated with dogs showing a non-reactive, non-aggressive response. The researchers concluded that these behaviors were consistent with peaceful or appeasing intentions, although they cautioned that their exact function requires further study.

This distinction matters.

If your dog licks their lips while another dog approaches, for example, they may not simply be "feeling anxious." They could also be communicating that they want the encounter to remain peaceful.

Similarly, a dog may lick their lips when a person bends over them, reaches toward their head, or hugs them. Humans may interpret the dog's stillness as tolerance or affection, while the dog may actually be quietly asking for more space.

That tiny tongue flick can therefore be valuable information.

An anxiety-related lip lick is often surprisingly quick.

The tongue may briefly flick over the nose or across one side of the lips before disappearing again. Some dogs produce only the very tip of their tongue.

Others may lick repeatedly when their discomfort increases.

In veterinary practice, I have often seen dogs arrive looking outwardly "well behaved" while displaying a succession of quieter stress signals. They sit perfectly still while their owner talks, but their ears shift backward, their head turns away from me, and the tongue flicks over the nose every few seconds.

That dog is communicating quite a lot without barking, growling, or trying to escape.

Research conducted during veterinary examinations supports this connection. One study found that veterinary examination produced measurable acute stress responses in dogs, including increased heart rate and significantly more lip licking.

This is one reason modern low-stress veterinary handling places so much emphasis on noticing the quieter signs before a dog feels forced to escalate.

No single body-language signal should be interpreted in isolation.

Research on canine communication emphasizes that individual behaviors need to be considered alongside the dog's posture, facial expression, surroundings, and what happened immediately beforehand.

A dog who licks their lips after eating peanut butter is probably dealing with peanut butter.

A dog who lip licks while somebody unfamiliar bends over them, meanwhile, deserves closer attention.

Signs that make anxiety a more likely explanation include:

• turning the head or eyes away

• ears pulled backward

• yawning when not tired

• panting when it is not hot

• trembling or shaking

• crouching or lowering the body

• tucking the tail

• pacing or repeatedly changing position

• freezing or becoming unusually still

• trying to leave or hide

• lifting a front paw

• refusing treats they would normally take

You may notice several appearing together.

Think of canine body language less like a single warning light on a car dashboard and more like a collection of gauges. One reading rarely tells you everything, but several moving in the same direction create a much clearer picture.

Every dog has their own triggers, but certain situations commonly produce lip licking and other displacement behaviors.

The clinic is almost a perfect recipe for uncertainty: unusual smells, unfamiliar animals, slippery floors, restraint, strange people, and occasionally uncomfortable procedures.

Lip licking is therefore very common in veterinary settings.

Interestingly, a randomized study evaluating dog-appeasing pheromone during veterinary examinations found that dogs exposed to the pheromone gel displayed significantly less lip licking while in the waiting room, although physiological stress measurements did not significantly differ.

That illustrates another important point: behavioral and physiological measures of stress do not always line up perfectly.

Dogs may lip lick when strangers approach directly, maintain eye contact, reach toward them, or lean over their body.

Humans naturally approach one another face-to-face. Dogs often find that intensity less comfortable.

Nail trimming, ear cleaning, brushing, bathing, or being physically restrained may cause repeated tongue flicks before a dog tries more obvious avoidance.

Watching for these early signs lets you pause before the situation becomes overwhelming.

Lip licking does not only occur during fear.

Studies have also observed nose and lip licking when dogs become frustrated, particularly when they expect a reward but cannot obtain it.

If your dog begins rapidly lip licking during a difficult training exercise, the lesson may have become confusing or frustrating rather than enjoyable.

Lip licking may appear during greetings or tense social encounters, particularly when another dog comes very close.

In these situations, it may contribute to non-confrontational communication.

Thunderstorms, fireworks, construction noise, crowded events, or unfamiliar surroundings may all trigger displacement behaviors.

Sometimes owners notice the lip licking before they notice any other sign that their dog is worried.

The most useful response is usually to determine what changed immediately before the licking started.

Did somebody approach?

Did a child hug the dog?

Did you pick up the nail clippers?

Did another dog enter the room?

Once you identify the likely trigger, increase your dog's sense of safety rather than asking them to simply tolerate increasing discomfort.

Where possible, create more distance from the trigger. Allow your dog to move away rather than holding them in place. During training, make the exercise easier. During grooming, pause for a moment. At the veterinary clinic, tell the veterinary team that your dog appears uncomfortable.

Repeated exposure to something frightening does not necessarily teach a dog that it is safe. If the experience remains overwhelming, repeated exposure can actually strengthen the fear response.

For persistent anxiety, desensitization and counterconditioning are often used. Desensitization introduces the trigger at an intensity low enough that the dog can remain comfortable, while counterconditioning pairs that trigger with something positive.

For example, a dog afraid of nail clippers might initially receive a treat simply for seeing the clippers several feet away. The process gradually progresses over many short sessions.

The aim is not merely to stop the lip licking. The aim is to change the underlying emotional response that caused it.

Never punish a dog for displaying subtle stress behaviors.

Lip licking is useful communication.

The same applies to turning away, moving away, growling, or other distance-increasing signals. If these warnings repeatedly fail to create space, some dogs eventually escalate their behavior.

Research examining companion-animal welfare describes subtle behaviors such as lip licking and gaze aversion as signals that can occur before more obvious defensive behaviors.

Rather than thinking, "How do I stop my dog doing that?" ask:

"What is my dog telling me about this situation?"

That question usually leads to better behavior and better welfare.

This is perhaps the most important caution in the article.

Repeated lip licking can have medical causes, and owners should not automatically assume a behavioral explanation.

Dogs commonly lick or smack their lips when nauseous.

The recently updated MSD Veterinary Manual lists lip licking, salivation, restlessness, vocalization, and lethargy among recognizable signs of nausea in dogs.

You may also notice repeated swallowing, drooling, loss of appetite, grass eating, retching, or vomiting.

Car journeys can make the distinction particularly confusing because dogs may experience both anxiety and motion sickness.

A fractured tooth, periodontal disease, mouth ulcer, foreign material trapped between the teeth, inflammation of the lips, or another oral condition may cause repeated licking.

Dogs with mouth problems may also develop bad breath, drooling, difficulty chewing, reduced appetite, pawing at the mouth, or sensitivity when their face is touched.

The MSD Veterinary Manual notes that oral and salivary disorders can cause drooling, difficulty swallowing, lip smacking, and other mouth-related behaviors.

Dogs experiencing stomach or esophageal discomfort may lick their lips repeatedly.

Nausea often precedes vomiting, with dogs becoming restless, salivating, repeatedly swallowing, and licking their lips before actually being sick.

Grass, plant material, fragments of toys, sticks, bones, or other foreign objects can occasionally become trapped around the teeth or underneath the tongue.

If your dog suddenly starts frantically licking their lips, pawing at their face, drooling, or struggling to swallow, their mouth should be examined.

Do not put your fingers deep inside the mouth of a distressed dog, particularly if you cannot clearly see the problem.

Occasional lip licking in an obvious stressful context is usually not an emergency.

Arrange a veterinary assessment if the behavior appears suddenly, occurs frequently without an obvious emotional trigger, or is accompanied by other signs of illness.

Seek prompt veterinary advice if your dog has persistent vomiting, significant drooling, trouble swallowing, refuses food, appears painful, repeatedly paws at their mouth, or you suspect they have eaten something toxic or swallowed a foreign object.

Non-productive retching, excessive salivation, restlessness, and a swollen abdomen can also occur with gastric dilatation-volvulus, commonly known as bloat, which is a veterinary emergency.

When in doubt, filming an episode can be extremely helpful. Dogs have an impressive habit of stopping unusual behaviors approximately three seconds before entering the veterinary consultation room, so a phone video can give your veterinarian valuable information.

Lip licking is one of those tiny canine behaviors that becomes surprisingly informative once you learn to notice it.

In an anxious dog, that quick flick of the tongue may signal uncertainty, emotional conflict, increased arousal, or an attempt to communicate peaceful intentions. Research increasingly supports its value as part of the broader repertoire dogs use when navigating uncomfortable social situations.

But it should never be interpreted alone.

Look at what happened immediately beforehand, what the rest of your dog's body is doing, and whether the behavior disappears once the stressful situation ends.

Most importantly, listen when your dog communicates quietly.

A dog who licks their lips, turns their head, or moves away is giving you an opportunity to make the situation easier before they feel the need to communicate more loudly.

And if the lip licking appears frequently outside stressful situations, particularly alongside drooling, vomiting, appetite changes, difficulty eating, or mouth discomfort, speak with your veterinarian. Sometimes the tongue is expressing emotion. Sometimes it is pointing toward a medical problem that deserves attention.