Dog Spitting Up White Mucus

All dogs vomit occasionally, so if your dog only does so once in a while it may not be a major cause for concern. But you should pay attention to your dog’s health—and, if your dog vomits, it’s a good idea to examine what comes out. For a more comprehensive look at conditions that could cause your dog to vomit, check out our guide. And if your dog vomits repeatedly or you have any reason to suspect they’re sick, contact a vet as soon as you can. In the meantime, here is some information about why there might be mucus in your dog’s vomit, and what you should do about it.

Your dog is most likely throwing up white liquid because there’s not much else in his stomach to purge. The white foam is a mix of saliva and beaten gastric juices. The mucus lining his stomach is irritated, becoming frothy, and that’s what you’re seeing come up onto your carpet or floor.

Why Do Dogs Vomit White Foam?

There are a few potential reasons why your dog is vomiting white foam. In many cases, your dog has simply tasted or eaten something that led to a stomach upset. Your dog might have been nibbling on grass, licking something with a bad taste, or chewing on something irritating. However, vomiting of any kind can indicate a more serious illness, especially if the vomiting occurs frequently.

  • Indigestion (often due to dietary indiscretion)
  • Acid reflux
  • Pancreatitis
  • Other gastrointestinal inflammation
  • Gastrointestinal obstruction
  • Megaesophagus
  • Toxin exposure
  • Infectious disease
  • Rabies (rare)
  • Bloat (this in an emergency; go to the nearest open vet if your dog has a distended abdomen, seems restless or painful, or keeps looking at their abdomen)
  • White, foamy vomit is often caused by excessive production and swallowing of saliva, which can be a symptom of nausea. Ingesting grass, plant material, or other things that are unusual or difficult for a dog to digest can cause vomiting. Toxins can cause GI irritation and worse, often leading to vomiting.

    Kennel cough and other upper respiratory problems may cause dogs to cough up foamy white liquid. The material may appear to be vomit but could actually be mucus and fluids from the respiratory system. Or, the dog might have swallowed mucus and fluid from the respiratory issue and be vomiting that up.

    Observe your dog—is there heaving? Or, is there retching and coughing, then spitting up of white foam? Either situation requires a vet’s attention, but these details can help your vet make the right diagnosis.

    What to Do If Your Dog is Vomiting White Foam

    If your dog vomits white foam just one time, there is no need for immediate concern. Watch your dog for weakness, lethargy, loss of appetite, diarrhea, and other signs of illness. If your dog seems otherwise normal, continue to watch for more vomiting. If the vomiting continues, withhold the next meal and call your vet.

    Contact your veterinarian if your dog vomits more than twice in a 24-hour period or if intermittent vomiting continues for more than a day. Also, contact your vet if other signs of illness accompany an episode of vomiting.

    Why Is Your Dog Vomiting White Foam?

    Common reasons for dogs vomiting white foam include excess gas or air in the stomach, digestive issues, bloat, but also more serious issues like kennel cough, kidney problems, or parvovirus.

    Excess gas or air in the dog’s stomach, which means there’s probably nothing left in your dog’s stomach to vomit, that’s why white slime is coming out.

    If your dog is throwing up puddles of bubbly, white foam, he may have eaten something he shouldn’t have, as dogs are so prone to doing.

    Or your pooch may have eaten in a hurry or exercised too soon after eating.

    The composition of the white foam is often a mixture of saliva and gastric juices.

    Sometimes the mucous lining becomes irritated and frothy, and your dog will start vomiting white foam.


    Why is my dog throwing up mucus and foam?

    If your dog has vomited white foam only once and is still happy and eating, this may just be a mild upset stomach. Keep them cool and relaxed and withhold food for 12 hours, to help calm their stomach. Monitor them closely for more serious symptoms.