If your dog keeps sticking their tongue in and out nonstop, it can be unsettling—especially when the behavior seems new, frequent, or out of character.
While occasional tongue flicking is normal, constant tongue movements often signal irritation or underlying health problems.
We outline the common reasons for constant tongue flicking in dogs, what you can do at home, and when to seek veterinary help.
Dog Constantly Sticking Tongue In and Out: Why It Happens
A dog constantly sticking its tongue in and out may be experiencing nausea, dental problems, dehydration, oral irritation, stress, neurological issues, or something lodged in the mouth. While some causes are mild, persistent tongue flicking can indicate discomfort that requires attention.
Dog Constantly Sticking Tongue In and Out: Common Causes
Nausea or Upset Stomach
Dogs often stick their tongue in and out when they feel nauseated. The action helps move saliva, ease mouth discomfort, and prevent drooling caused by stomach upset.
Nausea can stem from dietary changes, eating grass, mild infections, pancreatitis, or simply an empty stomach.
When nausea is present, the tongue flicking usually appears with lip licking, swallowing hard, pacing, or intermittent drooling. The dog may appear restless, hesitant to eat, or unusually quiet.
Even mild nausea can trigger repeated tongue movements as the dog tries to settle the unpleasant sensation. Because the tongue and stomach are neurologically linked, this pattern is one of the earliest signs that the digestive system is irritated.
Dogs experiencing acid reflux may show the behavior most often at night or early morning when stomach acid is highest. The repetitive tongue flicking becomes a coping response to the uncomfortable burning sensation rising into the throat.
Read more: Dog Startled For No Reason (Understanding sudden behavioral reactions)
Something Stuck in the Mouth or Teeth
If a dog has a foreign object lodged in the mouth—such as a piece of grass, plant seed, food fragment, hair, or string—they may repeatedly stick their tongue in and out in an attempt to remove it.
The movement becomes persistent because the dog feels something irregular or irritating inside the mouth.
Dogs with something stuck may paw at their face, rub their mouth on the floor, or chew oddly to try dislodging the object. Items like foxtails, burrs, or splinters can become lodged between the teeth or gums, creating a nagging sensation that triggers constant tongue flicking.
Even small debris can cause significant irritation if it becomes trapped under the tongue or between the back molars. Because dogs cannot communicate the discomfort, the repeated tongue movement becomes their primary signal.
Dental Pain
Dental problems are a major cause of constant tongue flicking. When the mouth hurts, dogs move their tongue repeatedly to avoid pressure on painful areas or to shift saliva around inflamed tissues.
Dental disease such as gum infection, loose teeth, fractured teeth, or abscesses cause chronic irritation that leads to repetitive tongue movements.
Dogs with dental pain may chew on one side, drop food, react to jaw touch, or resist having their mouth examined. They may develop a foul odor, swollen gums, or increased drooling.
Because oral discomfort gradually intensifies, owners often first notice subtle behaviors like constant tongue flicking before more obvious symptoms appear.
Senior dogs are especially prone to this cause due to years of tartar buildup and gum recession.
Dehydration
A dog who is dehydrated or experiencing dry mouth may constantly move their tongue to moisten it. Dry mouth can result from heat, medications, stress, or underlying illness.
When saliva production drops, the tongue feels sticky or uncomfortable, prompting the dog to flick it in and out repeatedly.
This behavior may become more noticeable after exercise, during warm weather, or when the dog has not been drinking enough water. Some medications—especially antihistamines, diuretics, and seizure medications—can reduce saliva and trigger constant tongue movements.
Dehydration causes the mouth tissues to lose lubrication, making even small movements uncomfortable. The tongue flicking helps dogs redistribute the limited moisture available.
Low Blood Sugar or Early Neurological Changes
Neurological issues can cause repetitive, involuntary motions, including constant tongue flicking. Seizure precursors, mini-seizures, or neurological inflammation may manifest as unusual mouth behavior.
Dogs may have subtle tremors, glassy eyes, or uncoordinated movements along with the tongue motion.
Hypoglycemia (low blood sugar) can also trigger strange oral behavior. When the brain does not receive enough glucose, dogs may act confused, tremble, or repeatedly flick their tongue as the nervous system becomes unstable.
This is common in small-breed puppies, diabetic dogs, or dogs who have not eaten for long periods.
If neurological involvement is present, the tongue flicking may appear paired with strange eye movements, stumbling, or sudden behavior changes.
Stress
Tongue flicking is a well-known canine calming signal. Dogs use it to communicate stress, nervousness, or discomfort in their environment.
When a dog feels overwhelmed, overstimulated, or uncertain, they may repeatedly stick their tongue in and out as a self-soothing mechanism.
This behavior may occur during vet visits, loud noises, new situations, social interactions, or moments where the dog feels insecure. Dogs may pair the tongue flicking with yawning, pacing, lowered ears, or averting their gaze.
Anxious dogs often display the behavior more frequently at night, when routines change, or when the household becomes hectic. Chronic anxiety can cause repeated tongue flicking even when no immediate trigger is visible.
Mouth Irritation
Exposure to plants, household cleaners, lawn treatments, or mild chemicals can irritate a dog’s mouth, causing them to flick their tongue repeatedly.
Dogs frequently lick surfaces, floors, or outdoor areas without the owner noticing, leading to mild burning or tingling in the mouth.
Common irritants include cleaning sprays, residues on floors, chemical deodorizers, citrus oils, or certain plants. Even mild irritation can create persistent tongue movements as the dog tries to soothe or remove the sensation.
Nasal or Throat Irritation
The tongue is closely linked to throat and nasal sensation. If a dog has post-nasal drip, throat irritation, or mild sinus inflammation, the strange sensation can prompt constant tongue flicking.
Dogs may swallow frequently, make gulping noises, or seem uncomfortable after drinking water.
Conditions like allergies, reverse sneezing, or mild infections sometimes cause mucus to accumulate near the soft palate. The dog identifies this as an irritating sensation and uses tongue movements to manage the discomfort.
Read more: Dog Constantly Reverse Sneezing (When irritation becomes chronic)
What to Do If Your Dog Is Constantly Sticking Their Tongue In and Out
Start by observing your dog calmly. Look for additional signs such as drooling, pawing at the mouth, swelling, or reluctance to eat. Gently check the outside of the mouth for debris, but avoid prying open the mouth if your dog resists, as this can cause stress or injury.
Offer fresh water to help soothe dryness or wash away mild irritants. If you suspect nausea, allow your dog to rest and avoid feeding large meals immediately. Soft, bland foods may help settle the stomach temporarily.
Assess whether your dog recently encountered grass, plants, household cleaners, new treats, or dental chews. Removing these potential triggers can quickly reduce symptoms. Keep your dog indoors if environmental allergies may be contributing, and wipe their face and paws after being outdoors.
Reduce anxiety triggers by giving your dog a quiet space, predictable routines, and opportunities for gentle interaction and reassurance. Avoid punishment, as this can worsen stress-based tongue behavior.
If the tongue movement persists, worsens, or comes with other symptoms, veterinary evaluation is needed to rule out dental disease, neurological issues, or internal discomfort.
When to Call or Visit Your Vet
Contact your veterinarian promptly if your dog:
• Continues sticking their tongue in and out frequently.
• Shows drooling, bad breath, or signs of dental pain.
• Refuses food, eats slowly, or drops food from their mouth.
• Vomits, appears nauseated, or has stomach discomfort.
• Shows swelling around the face or muzzle.
• Acts lethargic, confused, or disoriented.
• Appears dehydrated or weak.
• Repetitively flicks the tongue with no obvious cause.
• Recently chewed unfamiliar plants or objects.
Seek emergency care if:
• Tongue movements become rapid or uncontrollable.
• Your dog collapses or shows seizure-like symptoms.
• There is sudden swelling of the mouth or throat.
• Breathing becomes difficult.
Unusual tongue behavior can escalate quickly when linked to neurological or allergic reactions.
Read more: Dog Constantly Biting at Base of Tail (Here’s why)
Key Takeaway
A dog constantly sticking its tongue in and out may be experiencing nausea, dental pain, oral irritation, stress, or neurological changes. While occasional tongue flicking is normal, constant or repeated episodes mean something is bothering your dog.
With careful observation, environmental adjustments, and veterinary support when needed, most dogs recover quickly and return to comfortable, natural behavior.