Dog slobber is one thing, but is your dog drooling a lot?
Some dogs drool all day and are perfectly healthy. A Saint Bernard leaving wet patches on your jeans is just being a Saint Bernard. What matters is change: a dog that suddenly drools far more than usual, or a dog that never drooled and now does, is telling you something has shifted.
Vets call excessive drooling hypersalivation or ptyalism. It is a sign, not a disease, and the causes run from a cracked tooth or a car ride to a poisonous toad. How urgent it is depends on whether the drooling is new and what other signs come with it.
What Is Ptyalism in Dogs?
Ptyalism means more saliva is leaving the mouth than normal. According to the Merck Veterinary Manual, that happens in two different ways:
- The glands make too much saliva (hypersialosis). Nausea, some toxins and some medicines do this.
- The dog cannot swallow normal saliva (pseudoptyalism). A swallowing problem, something stuck in the mouth or throat, or a painful mouth lets ordinary saliva spill out.
A nauseous dog needs a different workup from one that can't swallow. Normal drooling happens when a dog smells or expects food, is excited, or is hot.
Dogs with heavy, loose lips, such as Saint Bernards, Mastiffs and Newfoundlands, and flat-faced breeds such as Bulldogs and Boxers, let saliva escape more easily without necessarily making more of it. For them the baseline is wet, and the warning sign is a change from that baseline.
Dry mouth (xerostomia) is the opposite problem: too little saliva. It is uncommon in dogs and does not cause drooling.
Why Is My Dog Drooling So Much?
The causes below follow Merck's grouping.
Mouth and teeth
Gum disease is the most common oral problem in dogs, and periodontal disease, fractured teeth, tooth root abscesses, mouth ulcers, inflammation of the mouth (stomatitis), injuries and oral tumors can all make a dog drool. Bad breath often comes with mouth inflammation, and the saliva may be tinged with blood. More on dog tooth problems.
Something stuck in the mouth or throat
Sticks, bone fragments and other objects can lodge in the mouth, throat or esophagus. The dog drools because it can't swallow properly, and it may paw at its mouth, gag or refuse food.
Nausea and the gut
Nausea is a classic drooling trigger. Inflammation of the stomach or intestines (gastritis, enteritis) can set it off, and so can motion sickness: some dogs drool heavily in the car and are fine once the ride ends.
Toxins, venoms and caustic burns
Merck lists toads, caustic household products, some plants, nicotine, slug and snail bait (metaldehyde) and organophosphate insecticides among the poisons that cause sudden, heavy drooling.
- Toads. In the US, serious cases mostly involve the cane toad (also called the marine toad) and the Colorado River toad. The ASPCA notes these toads are found in Florida, southern Texas, Hawaii and the southern parts of Arizona, New Mexico and California. Merck lists profuse, sometimes frothy drooling, retching, vomiting, weakness, trouble breathing, bluish gums and seizures among the signs. If your dog may have mouthed or licked a toad, call your vet or the ASPCA Animal Poison Control Center (888) 426-4435 now.
- Caustic products. Corrosive cleaners and chemicals burn the mouth and throat; the ASPCA lists drooling, vomiting, mouth ulcers and difficulty swallowing.
- Slug and snail bait. Metaldehyde poisoning causes drooling with wobbliness, tremors, seizures and a dangerously high body temperature.
Salivary gland problems
The most common salivary gland disorder in dogs is a salivary mucocele: saliva leaks from a damaged gland or duct and collects under the skin. It usually shows up as a soft, nonpainful swelling that slowly grows under the jaw or on the neck, or as a swelling under the tongue. A mucocele at the back of the throat can make breathing difficult. Inflamed glands (sialadenitis) and gland tumors are other possibilities.
Nerve and brain problems, and infections
Damage to the nerves that control swallowing, seizure disorders, the nervous form of canine distemper and rabies can all cause drooling, often because the dog can no longer swallow normally.
Liver and kidney disease
Severe liver disease (when toxins the liver should clear reach the brain, a condition called hepatic encephalopathy) and kidney failure can both cause drooling.
Heatstroke
Drooling, heavy panting, vomiting, diarrhea and weakness or collapse after heat exposure are signs of heatstroke, which Cornell's Riney Canine Health Center calls a medical emergency. Flat-faced, older and overweight dogs are at higher risk.
Fear, excitement and medicines
Fear, nervousness and excitement can make a dog drool, and some medicines cause it as a side effect. If it started with a new medicine, tell your vet rather than stopping the medicine yourself.
Skin trouble around the lips
Merck notes that constant drool can lead to moist, inflamed skin (acute moist dermatitis) on the lips and face if the area isn't kept dry. If that skin turns red, sore or smelly, ask your vet how to care for it. See common dog skin problems for what these changes look like.
When Is Drooling an Emergency?
- Normal for your dog: drooling that matches its usual amount and pattern.
- Book a vet visit: new drooling, or more than usual, that lasts or keeps coming back, even if your dog otherwise seems fine.
- Call your vet or an emergency clinic now: drooling together with any of the signs below.
Go now if drooling comes with:
- trouble breathing or swallowing;
- retching or vomiting;
- seizures, tremors or wobbliness;
- weakness or collapse;
- sudden swelling of the tongue (insect stings can do this);
- recent heat exposure;
- any possible contact with a toad, chemical, slug bait, medicine or other poison.
For a suspected poisoning, call your vet or the ASPCA Animal Poison Control Center at (888) 426-4435. It answers at any hour, and a consultation fee may apply.
A word on rabies. Merck notes rabies has been mostly eliminated in domestic dogs in North America, so it is rare in US pet dogs. It still matters here because one form causes heavy drooling and an inability to swallow, and people can be infected when they examine such a dog's mouth or give it medicine with bare hands. Once signs appear, rabies is fatal. If your dog is drooling and acting strangely, or isn't vaccinated against rabies, keep your hands out of its mouth and call your vet before you arrive. Read more about early signs of rabies in dogs.
What to Note Before the Vet Visit
You don't need to look inside the mouth. Note:
- when the drooling started, and whether it came on suddenly or built up;
- how it compares with your dog's normal drooling;
- the color of the saliva, any blood, and whether it is foamy;
- pawing at the mouth, gagging, trouble swallowing, vomiting or diarrhea;
- anything your dog may have chewed, licked or eaten, including plants, toads, cleaners, garbage, bones or medicines;
- any medicines or supplements your dog takes, and its rabies vaccination status.
How Vets Diagnose Excessive Drooling
Your veterinarian starts with the history. Merck advises that rabies be ruled out before the mouth is examined, so expect questions about vaccines and contact with wildlife first.
Next comes a full physical and oral exam. A painful mouth often can't be examined properly while the dog is awake, so your vet may recommend sedation or anesthesia.
Depending on what they find, your vet may run bloodwork and a urinalysis to check general health and organs such as the liver and kidneys. A suspected salivary gland problem can need imaging of the glands themselves, which Merck notes may include X-ray studies or CT.
Treatment Depends on the Cause
Your veterinarian treats the cause and chooses any medicine. Typical examples:
- Dental and mouth disease usually calls for a COHAT (comprehensive oral health assessment and treatment): a full dental exam, cleaning and treatment under anesthesia, sometimes with a veterinary dentist.
- A foreign body is removed, and any injury it caused is treated.
- Poisoning is handled with decontamination and supportive care at the clinic, guided by the toxin involved.
- A salivary mucocele is treated with surgery to remove the affected gland and its duct. Surgery is also used for some tumors and injuries, not as a general fix for drooling.
- Nausea, liver or kidney disease and other illnesses are treated at the source.
- If a medicine is the cause, your vet may change it.
- Irritated skin around the lips gets the care your vet recommends to keep it clean and dry.
Prognosis
The outlook depends on the cause and your dog's overall health. Drooling from a fixable cause, such as a dental problem or a lodged object, should settle once it is treated. Poisonings, heatstroke and neurologic disease can be serious, which is why speed matters with those.
Can You Prevent It?
Not every cause is preventable, but some risks are easy to cut:
- Keep cleaners, chemicals, slug bait, insecticides, medicines and toxic foods out of reach, along with bones, sticks and garbage.
- If you live where cane toads or Colorado River toads are found, watch your dog outdoors.
- Keep up with dental checkups and ask your vet which home dental care fits your dog.
- Protect flat-faced, older and overweight dogs from heat.
- Never give your dog human medicines unless your veterinarian tells you to.
- Keep rabies vaccination current as your veterinarian advises.
Conclusion
Drooling is normal for many dogs. A new or sudden change is the signal, and drooling with any emergency sign above means calling your vet now. If you share your home with a cat as well, see why cats drool.
Sources
- Merck Veterinary Manual: Salivary Disorders in Small Animals
- Merck Veterinary Manual: Disorders of the Mouth in Dogs
- Merck Veterinary Manual: Rabies in Dogs
- Merck Veterinary Manual: Toad Poisoning in Dogs and Cats
- Merck Veterinary Manual: Metaldehyde Poisoning in Animals
- Cornell University College of Veterinary Medicine: Heatstroke, a medical emergency
- ASPCA: The Trouble with Toads
- ASPCA: What Pet Parents Need To Know About Corrosive Household Products
- ASPCA: Animal Poison Control Center
This article is for general information and is not a substitute for advice from your veterinarian.
