Beethoven and Hooch were two canine movie stars that had two distinct talents… acting and drooling. In fact, drooling was part of their charming personas. But if you are the owner of a dog that constantly drips saliva on your lap, you may not always find it so charming. Consider why dogs drool and what we can do to deal with this annoyance.
The Biology of Drooling
Dogs, like people, produce a thick liquid inside their mouths called saliva. Saliva is composed of 98% water but also contains antibacterial compounds, enzymes, and electrolytes that are important to overall health. Glands near the jaw produce this enzyme-rich juice that empties into the mouth through ducts.
Saliva contains an enzyme called amylase that initiates the digestive process. Amylase mixes with food during chewing and breaks down food matter. Saliva also moistens the chewed food and helps form a bolus that aids in swallowing. Saliva constantly lubricates the mouth which improves the sense of taste. Plus, a moist mouth is more comfortable than a dry one.
In addition, saliva promotes dental health by bathing the teeth with proteins and minerals that protect tooth enamel and reduce gum disease. Saliva decreases the formation of cavities and prevents tooth decay by clearing food particles from the teeth. The antibacterial effects of saliva decrease the germs in the mouth that cause bad breath.
"While the production of saliva is normal, excessive production is not."
Overall, saliva is a good thing. But, too much of a good thing can be bad. While the production of saliva is normal, excessive production is not. When excess saliva is produced, the dog does not swallow it all. The saliva overloads the mouth, runs over the brim, and the dog drools.
Causes of Drooling
There are many causes of drooling or hyper-salivation. Some are normal and some indicate health problems.
- Food response: When you smell bacon frying or cookies baking, you may salivate. Your dog has over 200 million scent receptors, so he experiences the same, or even greater, reaction when he smells your food, his food, or even when he hears you open the dog food bag.
- Nausea: Yuk! Neither man nor beast likes to be nauseated. Regardless of the cause—gastrointestinal (GI) disturbances, vestibular (balance) problems, or car sickness—nausea is no fun. When nauseated, the dog’s salivary glands go into overdrive and he drools.
- Physical formation: Some dogs have mouths that make normal production of saliva appear excessive because the anatomy of their mouths allows the liquid to dribble out. Giant breeds are known for their saggy lips and drooping jowls that do not effectively hold saliva in and allow the liquid to run out. Think Bloodhound, Mastiff, St. Bernard, and Newfoundland as a few of the drooling breeds.
- Foreign bodies: When a dog gets something trapped in his mouth (wood fragment or plant matter), he drools. The offending object may be wedged between the teeth, often lying across the roof of the mouth, or embedded in the gum tissue. Dogs do not floss, so this is a common cause of drooling.
- Dental problems: Although saliva helps protect the teeth, dogs still develop dental issues. Tartar buildup traps bacteria and leads to gingivitis and periodontal disease. Inflamed or infected gums become sore and teeth become loose in the sockets as bony tissue erodes. Teeth may fall out or fracture, which can be painful. All of these dental problems result in hyper- salivation.
- Injuries: Abrasions from chewing hard objects (remember the stick that got lodged?), ulcers, cuts, and burns can cause excess drooling.
- Growths: Lumps or bumps in the mouth can cause drooling. These growths may be benign warts or cancerous tumors. Even harmless growths can result in drooling.
- Caustic agents: If your dog licks or eats something caustic or acidic, he may drool excessively. Think about tasting lemon juice and you will get the picture. Dogs are curious and often lap up household cleaners or snatch a lemon from the trash or nibble on a plant. All of these things can irritate the lining of the mouth and cause drooling.
- GI problems: Gastric reflux may send nasty fluids back up the esophagus and into the mouth which result in hyper- salivation. Hiatal hernias and megaesophagus (enlarged esophagus) can do the same thing.
- Excitement: Dogs drool when they get excited or agitated. That is why they slobber all over your guests!
Drooling Symptoms (besides slobbering!)
Drooling may be a symptom of an underlying problem. Here are a few other signs that may accompany hyper-salivation:
- Decreased appetite: If hyper-salivation is caused by chronic GI problems, the dog may experience a gradual loss of appetite. If nausea is the cause, the drooling may be temporary and cease when the upset stomach resolves. If the dog is drooling because of a mouth injury, growth, or foreign body, the drooling will not stop until the physical condition heals or the offending item/growth is removed. If the problem is dental disease, the appetite will not return until the oral issues are handled, i.e., teeth cleaned, teeth extracted, and/or gum infection cleared.
- Changes in eating routine: Dogs that love dry kibble may hesitate to eat when their mouths are sore. They may take small bites and chew cautiously, often on the least affected side. They may hold their heads at an odd angle in an attempt to position the food on the less painful side and may drop food from their mouths. They often eat better when served soft, moistened food.
- Changes in behavior: Even the sweetest dog may become aggressive when in pain. Other dogs become reclusive and withdrawn when they are hurting.
- Pawing at the face: In an attempt to alleviate the oral pain, some dogs rub their muzzles with their paws or on the floor. Difficulty swallowing. Drooling dogs with esophageal or stomach problems may gulp or extend their necks when they swallow food or water.
When investigating the cause of your dog’s drooling, your veterinarian will start with a complete physical exam, paying particular attention to the mouth. A simple survey of the oral cavity may point to a diagnosis and treatment plan; however, if nothing jumps out as the cause of drooling, your veterinarian may suggest blood tests, radiographs, or other diagnostic tests.
With so many possible causes of drooling, treatment plans will vary. Treating the underlying cause may include cleaning teeth, extracting teeth, removing growths, treating GI problems, avoiding irritants, healing injuries, removing foreign objects, or giving medication for nausea before you take a car trip.
"With so many possible causes of drooling, treatment plans will vary."
If the cause is behavioral, try settling your dog down before allowing guests to enter the house, or place the dog in a quiet area while you entertain visitors. Be ready for drooling when you cook dinner by having a towel handy to mop up the deluge.
If the cause is due to the shape of your dog’s mouth and there is not much that can be done about it, try tying a trendy bandanna on your dog to catch the slobber. After all, those flapping jowls give your bloodhound character, right? Then enjoy those wet, really wet, kisses.