Vomiting in Dogs: Causes and Vet Advice

Last updated 23 FEBRUARY 2023

This article is written by our in-house veterinarian, Dr Elise Barry, BVSc and last updated by Dr Gillian Hill, BVSc (Hons).

Vomiting is one of the most common reasons for dogs to visit the vet and owners should be familiar with common conditions that can lead to vomiting in their pet. There are some different aspects of vomiting in dogs that can help to pinpoint the cause.

Regurgitation vs Vomiting in Dogs

It's important to understand the difference between regurgitation and vomiting. Regurgitation is a passive process. The ingesta that is brought up is undigested and looks like the original food that was eaten. Regurgitation will occur directly after eating.

Vomiting is an active process where you will see your dog's sides heave and its stomach and upper intestinal contents forcefully expulsed. Vomiting occurs hours after eating and the contents can contain yellow bile (from the intestines), liquid or foam (saliva & stomach acid) and chunks (partially digested food). The vomitus also has a funky sour scent to it.

Vomit Colour

Colour is another important component to note in your dog's vomit. In some cases the colour can help to localise or narrow down the possible causes. It's also important to remember that dogs often eat a range of things they shouldn't, which can discolour the vomitus, so it is important to look at the colour of the vomit as just one part of the picture. In some cases, the reason for the vomiting can also be diagnosed by having a close look at the digested material - for example, bits of chewed up toys or foreign objects could signal an intestinal blockage.

Yellow Dog Vomit

Yellow, foamy vomit can indicate the presence of bile, indicating that the vomitus has come from the small intestine, just below the stomach. Just like in humans, bile is produced in the liver, stored in the gallbladder and then released into the duodenum - at the very top of the small intestine. Yellow vomit can be an indication of reflux of this bile, or underlying conditions such as intestinal diseases or liver disease.

Green Dog Vomit

Green vomit can be caused by similar conditions as yellow vomit, however toxins and poisons like rat bait can also turn your dog's vomit green.

Blood in Dog's Vomit

The presence of fresh red blood or digested blood ("coffee grounds" or "dregs") are considered serious complications, and an immediate trip to the vet is necessary. Causes of fresh or partially digested blood in the vomit can include blood clotting problems, ulcers in the gastrointestinal tract, gastritis (inflammation of the stomach), diseases of the oesophagus and bleeding lesions in the mouth.

Top 5 causes of vomiting in dogs

Dietary indescretion
Diet Change
Toxin/poison
Infectious agent (parasite/virus/bacteria)
Organ failure/disease

1. Dietary indiscretion

Some dogs are known for being garbage guts. They will eat indiscriminate food or objects whether it is rotting, another animal's faeces or even ingest entire objects (toys/bones) which can lead to gastroenteritis (stomach and intestinal inflammation) and vomiting. Some objects can even become stuck in the stomach or intestines and require emergency surgery for removal.

2. Diet change

Dogs can also vomit if there is a sudden change to their diet. New food may be introduced too quickly causing vomiting. Owners should always follow the 7-day guide to introducing new foods. This involves feeding one quarter of the new diet on the first 2 days with three quarters of the old food. On the second and third day half and half, then on the fourth and fifth day, three quarters of the new food and one quarter old food. And finally, on the seventh day the dog can be fed the new diet alone. This is just a guide and some dogs will need more gradual transitions.

Want to know more? Read How to Introduce a New Food to Your Pet.

3. Toxin/poison

Many household items can poison your pet and lead to vomiting and serious disease. Some of the list include common household insecticides, rodenticides (rat bait), chemical cleaners (house/lawn), prescription medication, plants (like azaleas and rhododendrons), food (chocolate, avocado and xylitol an artificial sweetener).

Want to know more? Read our article Dangerous Foods for Dogs and for a list of toxic plants, check out our Toxic Household Plant Guide.

4. Infectious agent

Infection caused by parasites (like intestinal worms), viruses or bacteria are also common causes of vomiting in dogs. It is always important to ensure your dog's parasite prevention and vaccinations are up to date as some of these conditions may be contagious or fatal.

Want to know more? Check out our article about Parvovirus and our Dog Worming Guide.

5. Organ failure/disease

Another common cause of vomiting is organ dysfunction. Diseases like pancreatitis (inflammation of the pancreas), kidney or liver failure, plus hormone dysfunction (endocrine disease) can all lead to vomiting.

Want to know more? Check out our articles about Pancreatitis, Kidney Disease and Liver Disease in pets.

How can I stop my dog vomiting?

If vomiting is persistent or frequent, or there are other symptoms such as lethargy or inappetance, we recommend a check up with your vet, so that the cause can be identified and treated appropriately.

If your dog has an occasional vomit, perhaps after eating something they shouldn't, or having a new food introduced too quickly, a bland diet such as poached chicken breast and boiled white rice can be offered for a few days, to help the gastrointestinal tract recover. If the vomiting resolves, their normal diet can then be reintroduced gradually, following the guidelines above.

Vomiting is a serious symptom of disease and if it is persistent or frequent or in conjunction with any other signs (like inappetence or lack of energy) then your veterinarian should be contacted.

Dogs with Sensitive Stomachs

Chronic mild or intermittent vomiting can be a sign of a sensitive stomach. If your dog is prone to tummy upset (and your vet has ruled out serious disease) take a look at our sensitive stomach diets.

For more information, take a read through our guide to the Best Sensitive Stomach Diets for Pets.

Shop all Sensitive Stomach Foods for Dogs

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