Why Is My Dog Throwing Up?


When your dog eats something noxious (such as the fried chicken he found in the bin) Mother Nature’s answer is to make the dog vomit. This is a protective mechanism whereby that two-day old fast food is got rid of from the dog’s stomach before it can make him seriously ill.

Of course, if you see your dog chowing down in the undergrowth, the reason for his sickness becomes obvious. But at other times the reason may not be so clear, and there many reasons why a dog might vomit.

When you take your sick dog to the veterinarian, in order to identify why he’s throwing up may mean running a whole raft of tests including blood work, radiographs, ultrasound, and endoscopy. Hopefully, an investigation isn’t always required, especially if there is a history of wrongdoing – such as our fast-food-loving scavenger.

My Dog Keeps Throwing Up

Your vet might prescribe a medication like Metoclopramide to ease your dog's vomiting, but this only addresses the symptoms.

Vomiting is a symptom of a problem, rather than a diagnosis in its own right, so let’s take a look at some of the reasons why a dog might throw up. You can also learn more about potential treatment options for your dog's vomiting here.

Foreign Bodies

Let’s start at the younger end of the age spectrum, with puppies, in our exploration of the unsavory subject of vomiting.

Youngsters are inquisitive and they also like to chew, which isn’t a great combination, because it increases the risk of a puppy swallowing something harmful. If what he swallows can’t pass along through the gut then it will cause a blockage – the technical term for which is a ‘foreign body’.

Think of a foreign body in the bowel as the doggy equivalent of a blocked drain in a sink – when you pull the plug the washing up water gets so far and then refluxes back up again. For our dog this means when he eats the food has nowhere to go and eventually he will throw up. Of course, foreign bodies are not solely the preserve of the young, but their nosey nature puts them at greater risk than older, more sensible dogs.

Food Poisoning

You guessed it; this is our scavenger snacking on illicit goodies. Hopefully Mother Nature does her job and has the dog throwing up whatever it was he ate, before the toxins are absorbed and make him seriously ill.

Parasitic Problem

Sticking with the youngsters, parasites are a common cause of sickness in this group. A heavy worm burden, especially roundworms, can irritate the bowel lining or in severe cases causes a blockage, leading to nausea and vomiting. These puppies may show other signs such as:

  • A pot belly
  • Dull coat
  • Ribs and pelvis appear bony
  • Poor appetite
  • Lack of energy

Infectious Causes

Any unvaccinated dog is at risk of picking up a life-threatening condition such as Parvovirus, distemper, or leptospirosis. Those most at risk are young unvaccinated dogs whose immune systems are weak and still developing. Some of the more serious conditions, such as Parvo, are associated with particularly unpleasant symptoms such as the dog vomiting blood.

Also be aware there are a whole spectrum of bugs which can cause stomach upsets which range in severity from mild to more serious. Always seek urgent veterinary attention for any dog throwing up blood, or that is not able to keep fluid down, or is lethargic or weak.

Sensitive Stomach

Some dogs suffer with a food sensitivity or allergy. This means their bowel reacts against certain foods, mounts an immune response, and labels the ingredient as harmful. The gut lining becomes inflamed and this causes symptoms such as vomiting and diarrhea, or even itchiness and skin infections. [£]

Symptoms of food allergy include some or all of the following:

  • Vomiting
  • Diarrhea
  • Weight loss
  • Itchy skin
  • Ear infections
  • Skin infections

Drug Side Effects

Happily, these days all drugs go through a rigorous series of tests before they are licensed as suitable for use in animals, but even despite this care, any drug can have side effects. Common medications, such as the non-steroidal anti-inflammatories (NSAIDs) used to treat the pain associated with arthritis, have a good safety margin but if given on an empty stomach can cause problems such as gastric ulcers. The classic sign of this is a dog throwing up blood. [%]

If you see blood in the vomitus, especially if your dog is on medication, contact your veterinarian immediately.

Health Issues

Whilst younger dogs are more likely to throw up because of a foreign body, infection, or worms, in older dogs the picture starts to shift. One of the body’s job is to safely get rid of the natural toxins that are the result of the digestive process. If, for example, the liver or kidneys are diseased, these toxins build up in the blood stream and make the dog feel nauseous and result in the dog throwing up. [*]

The list of conditions that can cause vomiting is a long one, and some examples include pancreatitis (inflammation of the pancreas), pyometra (womb infection), liver problems, kidney disease, inflammatory bowel disease, and uncontrolled diabetes.

My Dog Is Throwing Up

Contact your veterinarian if you notice the following signs:

  • Excessive thirst
  • Poor appetite
  • Vomiting
  • Weight loss
  • Lack of energy
  • Behavioral changes
  • Yellow staining to the gums, eyes, or skin

The Older Dog

Some older pets suffer from bilious vomiting syndrome. This causes the dog throwing up yellow foam, usually first thing in thing in the morning just after he’s woken up. This condition is not an illness as such, but the result of the dog having an empty stomach overnight and bile irritating the stomach lining, which makes him throw up. [*]

The solution is to offer him a meal just before bedtime, and offer a few dry biscuits the minute he gets up in the morning.

When To Seek Veterinary Help

Vomiting falls into two groups: those dogs who are taken ill in the short term (they suddenly start vomiting and can’t stop), and those with a longer-term problem (throwing up daily for a couple of weeks or more). [%]

If you are worried about your dog’s health, get him checked over by a veterinarian. Urgent attention is required for any dog vomiting blood, or that is dehydrated, in pain, listless, or jaundiced. Remember, if in doubt – contact your veterinarian and take their advice about whether the dog should be seen or not.


[£] Chronic vomiting in the dog. Delles. Waltham Focus 2 (14-19)

[*] Vomiting: Textbook of Veterinary Internal Medicine. Ettinger and Feldman. Publisher: WB Saunders

[%] BSAVA Manual of Gastroenterology. Thomas, Simpson, & Hall. BSAVA Publications.

There are no comments

Add yours