Get

In Your Inbox

Dogster is reader-supported. When you buy via links on our site, we may earn an affiliate commission at no cost to you. Learn more.

Why Is My Dog Foaming at the Mouth: 8 Common Reasons (Vet Answer)

Drooling-dog-panting-and-foaming

Have you ever noticed your dog foaming at the mouth? It is not a pleasant site, and it may not be immediately obvious what is causing it. While many people worry about rabies, this is relatively rare in many parts of the world, especially in vaccinated dogs. 

The other causes of foaming at the mouth vary from non-life threatening (such as stress, nausea, and dental disease) to very serious (such as heat stroke, seizures, and toxins). Below, we summarize the 8 most common causes of canine mouth-foaming. 

divider single dog paw oct 2024

The 8 Reasons Your Dog May Foam at the Mouth

1. Stress

Stress, anxiety, and excitement can all cause foaming at the mouth. This is the result of drooling and panting, sometimes combined with barking or vocalizing, which causes a dog’s drool to aerate and appear foamy. New people, unfamiliar dogs, loud sounds, visits to the veterinarian, and many other situations can cause stress for some dogs. 

Treating anxiety and avoiding stress is the only way to prevent this cause of foaming at the mouth. We recommend discussing this with your veterinarian in order to design a holistic stress-reduction plan.

Did you know you can talk to a vet online? Click on the image or button below to schedule a call: PangoVet_Mention-in-Content Savings V1



2. Nausea

When dogs feel nauseous, they drool. This can result in foamy saliva in and around their mouth. A full exploration of the causes of nausea in dogs is beyond the scope of this article. Common causes include gut upset, intestinal blockage (“foreign body”), car sickness, and medication reactions. 

Nausea is often accompanied by vomiting and lip-smacking, but not always. Nausea warrants a visit to the veterinarian; further investigation may be needed, though symptomatic treatment may also be appropriate (to stop them feeling so ordinary!).


3. Heat Stroke

Some dogs don’t know their exercise limits; other dogs, such as brachycephalic (flat-faced) breeds, struggle in hot conditions. Both of these factors can lead to overexertion and subsequent heat stroke. Panting and drooling lead to foam at the mouth, though many dogs suffering heat stroke will also collapse. 

Vomiting, diarrhea, and dehydration are common. In mild cases, managing heat stress is just a matter of stopping your dog from exercise, cooling them down, and ensuring they drink. Severe cases can be life-threatening, as organ damage occurs, requiring urgent veterinary intervention


4. Toxins and Poisons

Sick and unhealthy yellow Labrador Retriever dog coughing in a park or Kennel cough symptom
Image Credit: Dhanoo Surasarang, Shutterstock

Dogs are inquisitive by nature, and they are notorious for eating things they shouldn’t. Some non-food items that dogs eat or lick can cause foaming at the mouth, as the body has a significant inflammatory reaction to this substance.

Cleaning products, fertilizers, snail bait, and other chemicals can all cause foaming at the mouth, as can electrical burns to the oral cavity. Some frogs and amphibians will elicit a similar response if licked.


5. Dental Disease

Dental disease and oral health problems can cause foaming at the mouth. Again, this is due to excess salivation and subsequent aeration of saliva. The most common form of dental disease in dogs is periodontal disease.

This refers to plaque and calculus accumulation on teeth, leading to inflammation of the gums and sometimes tooth-root-abscesses. Broken and decayed teeth can also develop. Lumps and tumors within the mouth may cause similar signs.


6. Seizures

Dogs can experience seizures just like people can. The most common cause of seizures in dogs is epilepsy. Besides likely genetic links, it remains unknown what causes epilepsy in dogs. Other causes such as toxins, infections, and brain tumors can also cause seizures. Owners often report that their dog was foaming at the mouth when it had a seizure.

Additionally, seizures cause loss of consciousness, muscle spasms, paddling, and urination/defecation. Do not hesitate to call your nearest emergency vet if your dog has experienced (or is experiencing) a seizure.


7. Rabies

aggressive dog with excessive saliva
Image Credit: Victoria Antonova, Shutterstock

Thanks to the introduction of mandatory vaccination, the spread of rabies through North America has been largely halted. If your dog is vaccinated, rabies is very unlikely to be the cause of their mouth-foaming. Rabies is usually spread by biting from an infected dog.

Affected dogs also exhibit behavioral changes, aggression, seizures, paralysis, and inability to eat or drink. If you notice any of these symptoms, it is worth arranging a consultation with your veterinarian, even if rabies exposure is unlikely.


8. Normal Drooling

Despite all of the above causes of foaming at the mouth, it is important to remember that some dogs will foam at the mouth occasionally, and this is completely normal! This can be the result of normal drool that has become aerated, meaning lots of oxygen is getting into the saliva.

If it happens rarely, for a brief period of time, and your dog is otherwise completely fine, it may be reasonable to adopt a “watch and wait” approach.

divider dog paws 3 oct 2024

Conclusion

There are numerous causes of foaming at the mouth in dogs. Some of these are benign, and others are more sinister. If you notice your dog foaming at the mouth, remain calm; try to get a look in their mouth, and check for any other unusual signs.

As always, do not hesitate to contact your veterinarian for help.


Featured Image Credit: Reddogs, Shutterstock

How useful was this post?

Click on a star to rate (you can leave written feedback after clicking submit)

Help us improve Dogster for pet parents!

Your feedback really matters.

What did you like about this post? Also how can we improve it?

Join the conversation

2 Responses

  1. I can't afford emergency vet and my dog is real sick vomiting diarrhea and won't eat and I'm really worried it's been 2 days

    1. Hi Regina, I’m really sorry to hear that your dog is so sick—it must be such a stressful time for you. Vomiting, diarrhea, and not eating for two days are definitely concerning signs. If an emergency vet is currently out of your budget, we do have an online vet service that could be more affordable and our experienced vets can help you create a plan for care in the meantime. You can book a time that is convenient for you at this link here https://pangovet.com/schedule-appointment/. We look forward to speaking with and helping you and your dog.

Leave a Reply

You’re very welcome to leave a comment or question. Please know that all comments must meet our community guidelines, and your email address will NOT be published. Let’s have a positive and constructive conversation.

Talk With A Vet Online

Peace of mind,
anywhere, anytime

Affordable vet advice

Miniature Cocker Spaniel: Info, Pictures, Temperament & More

Have you ever wanted a lively, happy, and sweet dog as a pet? If yes, a Miniature Cocker Spaniel may tick all the...

German Shepherd Bloodhound Mix: Info, Pictures, Care & More

Loyal, intelligent, agile, and well-built, German Shepherds are the pride and joy of the canine world. Bloodhounds, in turn, are widely recognized as...

Homemade Dog Shampoo: 4 Simple Recipes

As Murphy’s Law would have it, your dog will likely find the one muddy spot in your yard when you are unable to...

6 Common Chihuahua Health Problems: Our Vet Explains

Chihuahuas have long been known as being small, vivacious companion dogs. Many people like them because they are not large, they’re easy to...

More related

Can Dogs Die From Fleas? Vet-Reviewed Facts & Prevention Tips

One of the most common health issues that dogs can experience is flea infestations. While these tiny pests may seem harmless, they can...

How Fast Can Shih Tzus Run? Average Speed & Breed Comparison

When you think about fast dogs, you likely think of the Greyhound. The Shih Tzu is not a breed that immediately comes to...

How to Have Safe Outdoor Fun With Your Dog at Night: 10 Vet-Approved Tips

You don’t have to limit having fun with your dog to daylight hours; you can have just as enjoyable a time at night....

Lab Husky Mix Dog Breed Guide: Info, Pictures, Care & More

The beautiful Siberian Husky and Labrador Retriever hybrid goes by several names: the “Labsky,” the “Huskadour,” or simply, the Siberian Retriever. As you’d...

Keep reading

8 Dog Smoothie Recipes Your Pup Can Enjoy Today

Dogs are omnivores that can enjoy many of the same fruits and vegetables that humans can eat. There are many potential benefits to feeding fruits and vegetables to dogs, as they’re refreshing snacks that are also packed with nutrients. Making...

Dog Smoothie Recipes Your Pup Can Enjoy Today

15 Dog Friendly Restaurant Chains: Take Your Pup Out For a Lunch

Eating out with your dog can be a ton of fun. It is a way to get out of the house and help socialize your dog. But which restaurants are dog friendly? Most restaurants that have outdoor patios will allow...

corgi dog in the restaurant

Open Farm Dog Food Review 2025: Our Vet-Approved Expert’s Opinion

If you’re looking for high-quality, human-grade dog food made with locally and sustainably sourced ingredients, then Open Farm may be the answer. This family-owned company arose out of a couple’s desire to feed their dog a nutritious meal made with...

Dogster_Open Farm Dog Food Review

Can Dogs Eat Star Fruit? Vet-Verified Info & Risks

Star fruit or carambola is an appropriately named southeast Asian fruit of the tree of the same name. It’s a global food item grown in the warmer USDA Plant Hardiness Zones of 10 and 11 in the United States.1 Its...

Can Dogs Eat_star fruit

What Fruits Can Dogs Eat? 13 Vet-Approved Options

Summer is right around the corner, and if you’re anything like me, you’re probably excited about all the in-season fruits you’ll be able to eat soon. You might also be curious about which fruits, if any, are safe to offer...

Labrador retriever dog eats watermelon from hands

Are Watermelons Good for Dogs? Nutrition Facts & Feeding Tips

As the weather gets warmer and your dog starts to pant, you may be looking for a refreshing treat that will cool you both down. If you’re snacking on a juicy watermelon, your dog might be begging for a piece....

watermelon-pixabay

10 Best Dog Foods for Shih Tzus in 2025 – Reviews & Top Picks

Shih Tzus don’t have their own specific dietary requirements, as such, but they are a very small dog breed so they need to get all of their nutritional requirements in a comparatively small amount of food and without too many...

shih tzu dog eating outdoors

Can Dogs Eat Beef Broth? Vet-Verified Nutrition Facts & FAQ

The internet is filled with articles about the benefits of bone broth for people, dogs, and cats. These sensationalist pieces proclaim that bone broth, including beef broth, is a wonder drug or a superfood. However, can dogs eat beef broth,...

Can Dogs Eat_beef broth