Dog drooling can be completely normal or a sign of a serious health problem. So, how do you know if your dog’s drooling is normal or if you need to worry? First, consider whether drooling is typical for your dog.

When is dog drooling normal? Your dog’s breed may play a role.

Some dogs drool and others don’t. Of the dogs that drool, some drool a lot and some drool just a little. Some breeds like Bloodhounds, Mastiffs, Newfoundlands and Saint Bernards are known for drooling, but dogs of almost any breed may drool from time to time.

Dog drooling is normal when dogs are anticipating something.

Dog drooling is also normal when it occurs as your dog is waiting in anticipation of something he really likes.

“I have Labradors and they drool often in anticipation for eating, playing or retrieving,” says Tracey Jensen, DVM, Dipl. ABVP, medical director at Wellington Veterinary Hospital in Wellington, Colorado. “That drooling is a part of their personalities. It’s something they’ve always done, it’s infrequent and it correlates with something they’re anticipating.”

When is dog drooling not normal? Anxiety could be a factor. 

Some dogs drool when they are nervous or anxious, even if they don’t typically drool. This type of drooling is often accompanied by panting and possibly trembling or other signs of nervousness. If your dog is drooling from anxiety, the drooling should stop once you remove the stressor.

Dogs may drool when they’re in pain. 

If your dog never drools or rarely drools, and you notice him drooling all of a sudden in the absence of a stressful situation, it could be a sign of pain (for instance, pain in the mouth or pain in the throat). In these cases, the drooling occurs because the dog doesn’t want to swallow the saliva in his mouth because it’s painful.

Oral pain might be caused by dental issues like periodontal disease, tooth infections or broken teeth, or by tumors in the mouth or throat area. Sometimes, dogs might get things like sticks or pieces of toys caught in their teeth or even embedded in the roof of the mouth, and this can cause pain and drooling as well.

Nausea might also make a dog drool.

Nausea is another common reason dogs drool. Again, they don’t want to swallow the saliva, so they just let it fall out of their mouths instead. If your dog drools in the car, he might be carsick. Other times, dogs become nauseous from stomach upset or some other gastrointestinal issue, or from another health problem.

“Any number of things outside of the gastrointestinal tract can cause a dog to be nauseous, including kidney disease and liver disease,” Dr. Jensen says. “The equivalent of vertigo in dogs can also cause dogs to be nauseous.”

Ingesting something toxic can cause dog drooling.

Finally, dogs can drool abnormally if they ingest something toxic like a poisonous plant, pesticide, chemical or toxic food. Dogs who are drooling because of a toxin usually have other serious signs like vomiting or diarrhea, shaking, seizures, bruising, bleeding or extreme lack of energy. Contact a vet ASAP.

What to do about dog drooling. 

If you notice your dog drooling and it isn’t part of his normal behavior, schedule a visit with your veterinarian to get him checked out as soon as you can. (Again, if you think your dog might have consumed something toxic, seek immediate veterinary attention.)

“Starting with the physical exam, [vets] will look for any indication of oral pain,” Dr. Jensen explains. “They may want to run simple laboratory tests to make sure that there are not any internal causes of nausea and they may want to do some imaging of the abdomen and even the throat area looking for anything that would cause them to not want to swallow.”

Tell us: Does your dog drool? What’s the usual culprit for his dog drooling?

Thumbnail: Photography ©fongleon356 | iStock / Getty Images Plus.

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