Why Is My Dog Vomiting Green Liquid?

Like people, dogs sometimes experience stomach upset that can lead to vomiting. If your dog is throwing up green material, he likely ate something green or is expelling bile from his stomach. A green color caused by a dietary indiscretion will usually resolve itself and isn't cause for alarm. Bile, however, could indicate a problem that requires a trip to the vet.

sick dog
Like people, dogs sometimes experience stomach upset that can lead to vomiting.
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Is it truly vomit?

Sometimes, dogs do vomit, but at other times, they regurgitate instead. While both are admittedly unpleasant to witness and gross to clean up, these two acts are quite different. When a dog vomits, he forcefully expels the contents of his stomach. The process is quite dramatic⁠ — you'll hear him retching and see his stomach muscles working to push the offending substance from his body.

Regurgitation is more subtle. Regurgitation occurs when the dog expels something that was stuck in his throat or mouth. Dogs regurgitate items before they reach the stomach, making them much easier to push out of the body. Your dog may make a coughing noise when regurgitating something, but you won't see his stomach muscles moving.

Green regurgitation likely indicates that your dog ate something green, got it caught in his throat, and coughed it back out. It's generally not a cause for concern unless it keeps happening. If it does, it's time for a trip to the vet.

Green vomit in dogs

No matter how vigilant you are, dogs sometimes find ways to eat things they shouldn't. When a dog's vomit turns green, it's often because she ate some grass or other plant material that disagreed with her. In this case, the vomiting will stop on its own in about a day. You don't need to see the vet unless the condition doesn't resolve itself.

Toys and poisons are exceptions, however. If there is any possibility that your dog is vomiting because she came into contact with a poisonous substance, take her to the vet immediately. Do the same if you think she ate a toy or nonfood item that is causing a bowel obstruction.

Recognizing bowel obstructions

Sometimes, dogs eat things that they can't digest or pass through their intestines. The item gets stuck instead of passing through the body, ultimately stopping the digestive process and making it impossible for the dog to eat or defecate. When this occurs, the dog will vomit.

At first, a blocked dog's vomit will likely contain bits of undigested matter and appear fairly normal. If he continues vomiting after emptying his stomach, bile is the only thing left for him to expel. A dog throwing up yellow slime or green liquid is likely doing just that.

A bowel obstruction is a medical emergency that requires treatment as soon as possible. In addition to vomiting, a blocked dog may refuse to eat, fail to defecate, show a decrease in energy, and experience stomach pain. If so, call your vet immediately.

A case of pancreatitis

Pancreatitis can cause vomiting in dogs and often has multiple symptoms, including a loss of appetite, dehydration, fever, a decrease in energy, and a hunched back. Pancreatitis is really just a fancy way to say that an animal's pancreas is inflamed and irritated. Often caused by consuming too much fat, pancreatitis is described as either acute or chronic.

In acute pancreatitis, a dog will eat something fatty that he shouldn't. Perhaps, for example, Aunt Florence was sneaking your pooch some juicy pork roast at the family dinner. In this case, the ingestion of the fat will trigger a sudden or acute attack of pancreatitis. After treatment with some fluids and medications, your dog will return to her normal healthy self.

Chronic pancreatitis is an inflammation of the pancreas that occurs slowly over time. Chronic pancreatitis is typically caused by an overall diet that is high in fat. In this case, your dog's food may contain more fat than it should, or Aunt Florence might come to dinner every Sunday to slip your dog a few unhealthy table scraps. In this case, a change in diet and a conversation with Aunt Florence are in order so you can get your dog on a low-fat regimen and make her pancreas happy again.

Diseases and infections

Vomiting is typically caused by something a dog ate, but it can indicate more serious health problems. If your dog vomits for more than 24 hours, it's time to take him to the vet and find the cause. Diabetes can cause vomiting in dogs, as can dietary allergies, kidney disorders, liver disease, cancer, and parasites.

All of these issues require a diagnosis from a veterinarian. Fortunately, your vet can cure many of these problems and manage the others to keep your dog happy, comfortable, and vomit free.

Other vomit colors

Sometimes, dogs get creative and vomit in colors besides the standard light brown, green, and yellow. If your dog is throwing up white foam, she may have bilious vomiting syndrome. In this condition, the bile naturally found in a dog's stomach irritates the stomach lining when it's empty. The problem is easily controlled by serving small meals throughout the day so the dog's stomach always contains a bit of food.

Red and black vomit are also possible. Both colors can indicate blood in the vomit, but the blood comes from different places. Red blood in vomit is fresh and usually indicates minor irritation in the stomach lining and isn't concerning.

Black vomit that looks like coffee grounds, however, indicates digested blood that's been in the stomach for some time. Upon closer examination, this vomit is usually more deep red than truly black and may signal that your dog has a stomach ulcer. Ulcers are painful and require veterinary treatment. Truly black or brown vomit often means your dog ate some dirt, and you have nothing to worry about.

Treating a vomiting dog

If your dog is vomiting due to an underlying medical issue, resolving the problem with your vet will stop the vomiting. You can treat your dog's vomiting at home, however, if it's simply a case of indigestion. Start by withholding food for 24 hours. Make sure that your dog has lots of fresh, clean water to drink during her fast.

After the fast, reintroduce food to your dog slowly. Start with rice or bland chicken since these foods are easy to digest, feeding small amounts throughout the day rather than offering one or two large meals. You can also offer your dog a bit of ginger to help calm her stomach. Treats containing the right amount are readily available at most pet stores.