5 Reasons Why Your Dog Is Throwing Up Bile

Jessica Remitz
Feb 17, 2017
4 min read
Image: Photo Grapher / via Image Bank


By John Gilpatrick

Vomit is unpleasant, and unfortunately, dogs do it all the time. Most dogs are eating machines and, unless you’re able to keep an eye on your pup 24/7, she’s probably going to scarf down something that she isn’t supposed to and chuck it right back up later.

One-off instances of vomiting are generally fine – unfortunate, but mostly not concerning from a health perspective.

The presence of bile, however, is a different story. This yellow-green substance is similarly unpleasant to clean up, but if it’s in your dog’s vomit – and especially if your dog starts vomiting bile with any frequency – you might want to have her checked out right away.

Here are five of the most common reasons why dogs throw up bile:

Bilious Vomiting Syndrome

“Bile is a fluid produced in the liver and stored in the gallbladder,” says Dr. Rachel Barrack, DVM. “Once food is ingested, it gets released into the small intestine and helps to breakdown food so the body can digest and utilize it appropriately.”

Bilious vomiting syndrome occurs when bile leaks into the stomach from the small intestine. This usually happens because a dog hasn’t eaten in a while or because she’s consumed an abnormally large amount of fatty foods. It can also happen if the dog has eaten a lot of grass or drank a lot of water.

“Typically, patients affected by bilious vomiting benefit from readily digestible, low-fat, high-fiber diets,” Barrack says. Additionally, you may want to consider smaller, more frequent meals for your dog, especially if the bilious vomiting occurs first thing in the morning, after a long period without eating.

GI Diseases

Bilious vomiting is a symptom of a number of conditions that affect the digestive system, including inflammatory disease, ulcers, parasite infections and certain cancers. In each of these cases, the underlying condition needs to be diagnosed and treated by a veterinarian to relieve the vomiting.

Because bile’s acidity can wear down the esophagus, it can lead to ulcerations if left unchecked. Breeds with sensitive stomachs that are pre-disposed to problems like this include bulldog breeds, toy breeds, retrievers and poodles, says Dr. Taylor Truitt, DVM.


Endocrine disorders like pancreatitis can occur after a dog ingests highly fatty or oily foods, Truitt says. This causes inflammation of the pancreas and, in turn, bilious vomiting, along with intense stomach pain and diarrhea. Pancreatitis usually occurs three to five days after ingestion of fatty foods, but can occur as early as 24 hours after.

Bilious vomiting due to pancreatitis will start between 24 and 48 hours after consumption of the fatty food.  To help treat this, vets will provide care to prevent against dehydration and electrolyte imbalances, Truitt says. During this time and for a few days following the diagnosis, feeding will stop to allow the pancreas to rest.

Intestinal Blockages

Truitt says toys, bones, and even large hairballs might create a blockage in the intestine. “These are emergencies and require immediate medical intervention,” she adds.

Regular vomiting turns bilious after the dog’s stomach has been emptied, but it’s ideal to address this problem before reaching this point. An extreme lack of energy and severe abdominal pain may indicate a blockage.

Surgery is the most common method for removal, Truitt says, but an endoscopic procedure can resolve some cases.


If your dog consumes something she’s allergic to, vomiting may occur and bile may be present.

Often, this occurs shortly after switching to a new food, and Truitt says owners who notice this should switch back to a food they know works for their dog right away. “Common food offenders include beef, dairy, wheat, egg, chicken, corn, lamb, soy, pork, rabbit, and fish,” she says.

In other cases, a dog may become allergic to something she’s eaten regularly for years. “Most pets develop food allergies within one to five years of age,” Truitt says, “but some pets move, and the change in the environment can trigger new allergies.”

In this case, a strict 12-week diet trial may be conducted to identify the offending protein. Owners can then work with a veterinary nutritionist to create a diet that removes this allergen without depriving their dog of the vitamins and nutrients it needs to function at full strength.

Concerned about your dog vomiting? Learn more about when dog vomiting is an emergency.

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