What to do when your dog won't stop throwing up

What to do When Your Dog Won’t Stop Throwing Up

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Most dogs will throw up at some time in their life. And while dog vomiting is unnerving, it isn’t always due to a serious medical condition. “Dogs tend to bounce back from vomiting more quickly than humans,” says Dr. Justin Shmalberg, a DVM and NomNomNow’s veterinary nutritionist. “Some may even try to eat right away.” Still, vomiting is a symptom, and the causes can range from mild to severe. Both extended vomiting or a dog throwing up intermittently and chronically usually indicates an underlying issue.

Here we’ll cover different reasons dogs vomit when you should be concerned, what to do when your dog keeps throwing up, and more:

Vomiting vs. Regurgitation

Though the terms are often used interchangeably, dog regurgitation and dog vomiting have very different definitions, and often very different causes.
With vomiting, the material that comes up from the stomach, and the process involves active abdominal contractions. That means when a dog is about to vomit you can usually tell. You might hear him make a retching noise, see his abdominal muscles working, or noticed that he’s hunched over, drooling, or licking his lips. When vomit comes up, it’s often coated with yellow bile, or, if it’s been in the stomach longer, it’ll be already digested.
Regurgitation is a process in which food comes up from the esophagus or pharynx, usually without any warning, and without abdominal contractions. The regurgitated material is may be coated with heavy amounts of saliva and mucus, and, when it’s food, it generally looks completely undigested.
To add confusion, if your dog starts coughing and brings up foamy material or mucus, this is probably expectoration, which stems from respiratory causes rather than issues with the gastrointestinal tract.
Below we’ll focus on the more common and concerning signs of a dog vomiting.

Dog Vomit Causes

If your dog keeps throwing up, you’ll want to identify why it’s happening. Here’s a rundown of some potential causes, starting with the most common at the top. Any dog throwing up persistently should go in for an exam—your vet can help determine what’s behind the problem, and how to treat it.

Diet-Related Causes of Vomiting


  • What it is: Inflammation of the stomach and intestines. Gastroenteritis is the most common cause of vomiting, though it’s worth noting that many acute conditions (aka those that are severe and sudden in onset) get placed in this category, because it can very difficult to determine their underlying cause.
  • What causes it: Typical causes are either a sudden change in the dog’s diet, or the dog ingested trash or other foreign material.
  • Symptoms: A dog with gastroenteritis will usually experience vomiting, diarrhea, or both, and may show temporary shifts in intestinal bacteria or the microbiome.
  • Prevention and treatment: Make any changes to your dog’s diet slowly—especially if the new food is very different in composition than the previous. And as always, discourage your dog from ingesting foreign material. Gastroenteritis usually resolves itself without any treatment, but fasting may be helpful.

Food allergy

  • What it is: A condition in which a dog’s immune system attacks a certain component of her food, usually an animal-source protein. Food allergies—which tend to show up in the form of skin or gastrointestinal problems—aren’t as common as most pet parents believe, and far less common than gastroenteritis or food intolerance.
  • What causes it: An abnormal response of the dog’s immune system to components of the food.
  • Symptoms: Vomiting, which may happen immediately after the dog ingests the triggering food or may be delayed 3 days. You also may notice skin signs, like excessive scratching or visible irritation (bumps, redness, etc.).
  • Prevention and treatment: Determining which food or foods your dog is allergic to is the hard part, and usually requires a food trial; read more about that here. After you identify the offending food or foods, eliminate them from your dog’s diet.

Food intolerance

  • What it is: Unlike a food allergy, the immune system is not involved in a food intolerance—the latter has more to do with the digestive system. But the signs of the two can look pretty similar, again, in the form of skin or gastrointestinal problems.
  • What causes it: The underlying reasons for an intolerance aren’t clear. It may be due to a sensitivity either to specific compounds or levels of certain nutrients, like fat, in particular foods. (Fat, for instance, is known to make the stomach empty more slowly, which could explain why it impacts digestion in some dogs.)
  • Symptoms: As with food allergies, you may notice vomiting after the dog ingests the triggering food, or notice skin signs.
  • Prevention and treatment: Once again, detection of a food intolerance requires trial and error. After you identify the offending food or foods, eliminate them from your dog’s diet.

Bilious vomiting syndrome

  • What it is: A sensitivity to the bile present in the dog’s own stomach, especially when a dog hasn’t eaten in a while.
  • What causes it: When dogs have this syndrome, it appears that the bile causes inflammation. These dogs may have higher amounts of bile in the stomach, too, due to reflux from the intestine.
  • Symptoms: The most common symptom is daily or intermittent vomiting, usually starting 6 or more hours after the last meal. For example, dogs will often vomit in the morning before owners have a chance to feed them. The vomitus is generally yellow and liquid, without any food.
  • Prevention and treatment: Feeding your dog more frequent meals, especially one late at night, can help manage the symptoms.


  • What it is: A condition characterized by inflammation in the pancreas, an organ responsible for secreting digestive enzymes that help to break down fat. Dogs may have acute pancreatitis (a single episode) or chronic pancreatitis.
  • What causes it: Pancreatitis is usually associated with the quick introduction of a diet much higher in fat diet or an instance of dietary indiscretion (e.g. your dog downs a pan of turkey grease on Thanksgiving when you’re not looking). But the underlying scientific predispositions that cause some dogs to develop this condition on high fat-diets are unclear and somewhat unpredictable.
  • Symptoms: Repeated vomiting, diarrhea, a hunched back, bloating or distention of the stomach, loss of appetite, lethargy, and fever. Chronic cases are characterized by chronic inflammation and fat intolerance, which your vet can measure with a blood test.
  • Prevention and treatment: As with preventing gastroenteritis, avoid sudden changes to your dog’s food. Dogs with the acute pancreatitis often go back to eating their normal diets; dogs with chronic pancreatitis often need to switch to a long-term low-fat diet.

Food-based toxins
Some foods people eat regularly are toxic to and can cause vomiting in dogs. You can find a brief list of foods dog should avoid here, including alcohol, caffeine, chocolate, macadamia nuts, and the sweetener xylitol.

Environmental Causes of Vomiting

If you rule out diet-related causes and still find yourself wondering, why is my dog throwing up?, it could be related to something in his environment. Below are some common environmental triggers.
Foreign object ingestion
Dogs with sudden and chronic vomiting may have eaten something they shouldn’t. “Many dogs aren’t discriminating. Toys, rocks, underwear—you name it, and dogs will swallow it,” says Shmalberg. “These things can get stuck in the outflow of the stomach or in the intestine, which causes a backup—and vomiting follows.” If your dog is known to gobble up anything in sight and/or you notice a certain object has gone missing, watch your dog carefully and get him to the vet if vomiting persists.
As a cause of vomiting, parasites are most common in puppies but can occur in dogs of any age. When a dog eats an animal host—beetles, cockroaches, etc.—he could pick up a relatively uncommon stomach worm that may cause vomiting. And while the word “parasite” usually makes us think of worms, there are some microscopic parasites like giardia that can cause vomiting. The best course of prevention of all of the above? Routine deworming and fecal examinations.
Just like foreign objects, if a dog gets into—and ingests—certain potentially harmful substances, that can cause a toxic response that starts with vomiting. On the list: chemicals, cleaners, fertilizers, antifreeze (which causes kidney failure), topical flea and tick medications, and even certain plants. For instance, sago palm toxicity—most prevalent in the south—can induce vomiting and even be deadly. But there are more common plants (like the tomato plant, though the fruit itself is OK) that could cause problems. Check out a list here. If your dog has had exposure to any of these right before vomiting, call your vet or contact ASPCA poison control for more information.
While any drug or supplement given orally can cause sensitive dogs to throw up, some are more likely to trigger it than others. These include:

  • Flea and tick preventatives given orally
  • Non-steroidal anti-inflammatory drugs used to help manage pain
  • Cyclosporine, which is prescribed for allergies and other immune-mediated conditions

Your vet will usually talk to you about vomiting before administration. And if your dog does vomit after taking a new drug, that doesn’t always mean a crisis. Try giving the medication with food, or even just giving him some time to adjust to it—that may be enough to help it go down easier.
Infections (other than parasites)
What can cause a dog to throw up or experience other gastrointestinal symptoms, too, are certain types of bacteria. Take salmonella, for example, which is a common cause of foodborne illness in people and certainly a risk factor for pets. Cooking food thoroughly is one way to avoid it—so if your dog eats a raw diet, this is just something to be aware of.
Then there are vomit-inducing viruses. Parvovirus is the most common,and usually affects unvaccinated puppies. And fungal infections that affect the gastrointestinal tract are rarer in dogs but do still occur, usually—but not always—in those who also have diarrhea and a history of weight loss.

Health-Related Causes of Vomiting

Vomiting may also be associated with the following health conditions—many of which can be life-threatening. As always, see your vet for proper diagnosis and treatment.
Gastric dilitation or gastric dilatation-volvulus (GDV)
This condition, sometimes referred to as gastric torsion or bloat, is a fast-progressing and potentially life-threatening condition in which an animal’s stomach dilates and then twists around its short axis. It’s an issue usually in large breed, deep-chested dogs, and the exact cause is unknown—likely it’s a mix of factors including the dog’s genetics, anatomy, and environment. With GDV, a dog will often act like they want to vomit but can’t, or they regurgitate after the stomach twists on itself. If your dog is dry-heaving, seems extremely uncomfortable, fits the breed type, and appears to have a severely distended abdomen, get her to the vet ASAP.
Hemorrhagic gastroenteritis (HGE)
Unlike common gastroenteritis, HGE is a life-threatening form of the condition characterized by vomiting and massive amounts of diarrhea with large amounts of fresh blood. Most cases occur suddenly without warning in otherwise healthy dogs; and it’s more common in smaller breeds. You’ll generally know something is very wrong if your pet ever has the misfortune of having HGE—she’ll appear severely ill. Fortunately the condition seems to run its course in a few days if the dog gets proper supportive care, including intravenous fluids.
Inflammatory bowel disease (IBD)
IBD usually happens when there are abnormal amounts of immune cells in the lining of a dog’s intestines and/or stomach. The most common symptom is chronic and occasional diarrhea, but chronic vomiting may also occur (alone or with diarrhea).
Cancer can cause just about any symptom in dogs. If your pet is vomiting long-term without a clear explanation, your vet might look for underlying tumors or cancers.
Kidney disease
The hallmark of chronic kidney disease is generally increased drinking and urinating. However, if toxins that the kidneys normally filter out build up in a dog’s system, vomiting can occur.
Liver and/or gallbladder disease
Infections and inflammation in the liver and gallbladder can certainly cause vomiting. And in a condition known as a gallbladder mucocele, more common in certain breeds like the Sheltie, vomiting may be the sole symptom.
As in humans, diabetes is a disease related to metabolism. Diabetic dogs often vomit, along with showing other symptoms, like drinking and urinating more, before they’re diagnosed.
Infections of the stomach and intestines are certainly possible, but they’re not as often a cause of chronic vomiting as you might think. Typically, dogs will clear harmful bacteria or require acute treatment for infections like salmonella. It’s more common that certain bacteria overgrow their normal populations, causing an imbalance in the GI tract known as dysbiosis; dysbiosis may cause an upset stomach.
Adrenal dysfunction (Cushing’s or Addison’s disease)
Every dog’s body produces stress hormones, and the levels can vary over time. However, if your dog is chronically producing too few (Addison’s disease) or too many (Cushing’s disease), either condition can cause vomiting.

Dog Vomit Color Guide

At this point, you may be wondering about dog vomit color—in other words, does black vomit mean something different than red vomit? According to Shmalberg, the color of vomitus isn’t always important. “It can be influenced by foods of a certain color, or whatever the dog recently ingested,” he says. “If a strange color isn’t due to something was recently ingested, the color may be significant.”
Use the information below as a dog vomit color guide, but remember, it can be hard to tell exactly what’s in vomit regardless of its color. You and your vet will have to use other clues—how frequently vomiting occurs, if it’s affecting appetite, if your dog also has diarrhea—to determine the severity.

Black Dog Vomit

A dog vomiting black isn’t very common. Often, it’s black vomit is benign and related to digging around in the dirt or eating soil. It can be a sign of a larger problem, though, if it represents digested blood. Digested blood looks like coffee grounds and is typically very dark red—but may appear almost black. It could indicate a stomach ulcer or possibly a toxin.  If your dog is vomiting black material and appears unwell, have your vet check it out.

White Dog Vomit

Is your dog throwing up white material? First you want to determine that what’s coming up is actually vomitus. It may instead be the result of expectoration, or coughing up material that comes from the throat or airways. A regurgitating dog may also bring up saliva that was pooling in the esophagus.
If, however, you’ve confirmed the signs of vomiting, then white vomit may mean that your dog:

  • …may just have an upset stomach. Many cases of gastroenteritis can cause vomiting when the stomach is empty, leading to white vomit.
  • …just ate grass or a small amount of another foreign material. This can induce vomiting, but if your dog hasn’t recently eaten, the vomit may just come up as white material with little to no substance.
  • …has bilious vomiting syndrome. In dogs with this condition, the presence of bile in the stomach (especially when he hasn’t eaten in awhile) causes irritation and induces vomiting—usually the vomitus is white, yellow-tinged, or bright yellow.

In any case, keep an eye out for a worsening of symptoms.
On the other hand, a dog vomiting white foam, especially if he seems like he’s trying to vomit and can’t, could be a sign of bloat or gastric dilatation-volvulus. With the latter, dogs will generally become very sick very quickly—although rare, it’s a medical emergency.

Red Dog Vomit

Red dog vomit is usually alarming to owners and understandably so. Unless your dog ate something that happened to be red, it’s usually a sign of fresh blood. It’s important to know that even a small amount of fresh blood can make vomit look like there’s a ton of blood, when usually, there isn’t that much. “It’s almost unheard of for an animal to lose enough blood through vomiting alone to cause trouble,” says Shmalberg.
Any irritation to the lining of the stomach or esophagus (including ingested foreign items) can cause short-term vomiting with blood, known as hematemesis. Often, dogs will vomit initially without blood, and then as the irritation increases, blood shows up. Similarly, gastritis (inflammation of the stomach) may cause red vomit with blood present. If it happens a single time, and/or the amount of blood appears small, it may not be cause for alarm.
Digested blood, however, generally indicates that blood has been in the dog’s stomach longer, and may point toward a stomach ulcer. If you notice your dog’s vomit is dark red to black in color, and/or congealed together (it may look like coffee grounds), talk to your vet. With a dog vomiting bright red blood (i.e. the vomit looks like pure blood), you should also call your vet immediately. Though rare, some toxins, like rat poison, can impact the blood’s ability to clot; this needs treatment as soon as possible in case there’s bleeding elsewhere.

Green Dog Vomit

Assuming your dog didn’t get into some green frosting, there are two major causes of green dog vomit, neither of which necessarily indicates a major issue.

  1. Plant material: Dogs frequently ingest plant material when they go outside, grass being the most common. It’s not clear that eating grass causes vomiting. But when grass is present in the vomit, the chlorophyll inside will often stain the liquid parts of the vomit—saliva, bile, digestive enzymes, acid—various shades of green. And while some dogs seem to vomit more readily after eating grass than others, ingesting grass and subsequent vomiting isn’t necessarily a sign of a major health issue.
  2. Bile: Green vomit may also indicate the presence of bile. Dog bile is made up of components from liver cells and is stored in the gallbladder. After a dog eats, the gallbladder releases bile into the upper part of the small intestine, where it’s designed to help with the absorption of fat and other nutrients. Some of this bile may reflux up into the stomach. This can actually cause vomiting (as in bilious vomiting syndrome), or, if the dog throws up due to another reason, the vomit may be tinged green. Typically, a dog throwing up green bile means that the bile is also fresher. That could indicate a lack of movement or obstruction in the intestines, which may require intervention. If your dog suddenly vomits green and seems unwell, see your vet.

Yellow Dog Vomit

Is your dog vomiting yellow? That, too, is usually a sign of bile (perhaps in lower concentrations than if the vomit appears green). Still, check out the advice covered above.

Brown Dog Vomit

Dark brown dog vomit that has a very strong and objectionable odor can occur when your dog eats something she shouldn’t, including her own or another dog’s feces (the term for this is coprophagia). But it could also indicate a block in the intestines, or that material is refluxing from the intestinal tract up into the stomach. If you notice your dog vomit brown, and he appears sick or is vomiting very frequently, have your vet take a look.
Dog Vomit Color Guide

How to Treat Vomiting in Dogs

The best way to approach how to treat vomiting in dogs is to identify the underlying cause. If your dog is throwing up due to a food allergy, chronic disease, or some other condition, treating that is critical. But even with veterinary help, it’s not always easy to find the cause because there are so many possibilities. If you or your vet have determined that your dog is healthy and not experiencing any other concerning signs, there are a few simple strategies that can help. Just be sure to get your vet’s OK before giving any medication, even if it’s over-the-counter.
The presence of food in an irritated stomach often causes more vomiting. That means you can try fasting your dog for 24 hours, while offering plenty of access to water—watch her to make sure she’s drinking. (For bilious vomiting syndrome, however, feeding more frequently is often the solution.)
Monitoring and/or adjusting diet
Diet can serve as both a treatment and preventative for vomiting. Start by finding a diet that agrees with your dog and feeding on a routine schedule. A few other things to keep in mind related to your dog’s food:

  • Generally, after vomiting, you should reintroduce food slowly in smaller, more frequent meals.
  • Variety is great, but always introduce new foods slowly. When treating vomiting in dogs, your vet may recommend a highly digestible diet (if she’s not already on one), like a fresh or home-prepared diet made with lean meats like poultry and rice or potato. (More digestible foods may help to prevent excess material from reaching the large intestine and stimulating diarrhea; and/or empty more quickly from the stomach to prevent vomiting.)
  • Lower-fat diets may help too, because they empty more quickly from the stomach and reduce the amount of bile released into the intestines.

Over-the-counter remedies
Unfortunately, there aren’t many effective anti-vomiting medications for dogs available over the counter. A temporary reduction in stomach acid could help ease vomiting, and while certain antacids like famotidine (Pepcid) do not appear to be very effective in dogs, others like omeprazole (Prilosec) and its prescription cousins may work. For a dog, the appropriate dose is about 0.7 mg per pound of body weight twice daily; be sure to give the closest whole tablet size, as crushing tablets can render them ineffective.
Ginger, too, has natural anti-nausea properties and may help to relieve vomiting in dogs in some cases; see dosing information here.
Probiotics, aka “good bacteria,” may help some cases of vomiting, especially those related to infection or inflammation in the dog’s stomach and intestines, and/or when the dog also has diarrhea.
Prescription medications
Maropitant (Cerenia) has more recently become a common anti-nausea medication for dogs that appears to have a wide margin of safety—your vet may prescribe to help relieve symptoms it if there’s no underlying cause for concern. (Ondansetron, metoclopramide, and other drugs have been available for a longer period of time.)

Puppy Vomiting

It’s hard to watch a puppy vomiting! Yet it seems like little ones throw up more often than adult dogs—probably due to their mischievous nature as they explore their new environments and gobble up items they shouldn’t. If you have a pup and observe vomiting, here are a few things to keep in mind:

  • Puppies frequently develop gastroenteritis from a food change or ingesting plant material or off-limits human food. As with adult dogs, if it’s a single episode of vomiting and your puppy is otherwise doing fine, it shouldn’t be a problem.
  • Many puppies don’t stop at food, ingesting all sorts of objects. If these items are of the right shape and made of nondigestible material (e.g. clothes, rubber toys, etc.), they can get stuck in the outflow of the stomach or the intestines and cause persistent vomiting. When this happens, a puppy will usually start to slow down and show signs of dehydration—a vet can do a radiograph or ultrasound to show whether or not there’s an object stuck. If so, a surgery or scoping procedure may be necessary.
  • Certain infections occur more commonly in puppies than in adult dogs. One of these is a severe infection known as parvovirus, generally characterized by both vomiting and diarrhea. Puppies with parvovirus can become dehydrated rapidly, and often need fluid therapy from a vet and other supportive treatments. If your puppy came from a litter with other puppies who were sick, or if he hasn’t had all of his vaccinations, it’s a good idea to have him checked for parvo. And don’t forget parasites—some can be transmitted by the mother as well as between puppies, and puppies tend to have higher amounts of parasites than adult dogs and more dramatic side effects. All of this underscores why routine vet checkups are recommended for puppies.
  • Rarely, puppies display chronic vomiting. This could indicate an infectious cause, food allergy, or congenital disorder. If your puppy has chronic vomiting, even if he’s acting normally otherwise, see your vet.
  • The treatments for vomiting in puppies are very similar to those for adult dogs. However, if you’re going to try a fast, keep it to 12 hours instead of 24, since pups have less stamina.

When Dog Vomiting Is an Emergency

Fortunately, most causes of dog vomiting aren’t emergencies, nor will they need long-term care. In the following situations, it’s usually safe to wait a bit to see if the episode passes before seeing a vet:

  • Dog vomits only once; or a few times over the course of an hour or two, and then stops
  • Dog acts normal after throwing up, e.g she runs around after vomiting or wants to eat right away
  • Vomiting is associated with some factor that’s easily explained—that is, a changes in diet; new medications (like flea treatments, antibiotics, heartworm prevention, etc.); or a dog getting into the trash or swallowing a foreign object

If you notice any of the following, though, it’s time to talk to your veterinary team:

  • Frequent vomiting lasting longer than 24 hours in duration
  • A dog throwing up blood—large amounts of fresh blood or any amount of digested blood (which appears darker) are both cause for concern
  • Vomiting that produces signs of dehydration (the gums are tacky rather than moist, the skin on the back doesn’t spring down quickly when pinched up) or a dog vomiting all the water they try to consume
  • Dog appears weak or lethargic after vomiting
  • Dog has a known history of toxin or foreign body ingestion
  • Dog appears to try to vomit but doesn’t produce anything and seems unable to throw up (remember, if it’s a large breed, deep-chested dog, bloat may be a possibility)

Oregon Veterinary Specialty Hospital (OVSH) has been serving the Portland and Beaverton area community since 1979. Dr. Robert T. Franklin (Internal medicine) welcomes referrals from veterinarians all over the Pacific Northwest. Our goal is to help your pet regain health and live a long and happy life.

Oregon Veterinary Specialty Hospital

9339 SW Beaverton Hillsdale Hwy,
Beaverton, OR 97005.
Phone: 503.292.3001
Fax: 503.292.6808
Email: [email protected]