Dog Vomiting Blood – Symptoms, Causes and Diagnosis

Key points

• Bloody vomit can be due to a variety of causes ranging from mild to severe
• The amount of blood and the presence of other symptoms help to decide how severe the problem is
• Exposure to toxins, the presence of a foreign object in the stomach, and cancers are all serious causes of dogs vomiting blood
• Dogs vomiting blood should always be evaluated by a vet to ensure the cause isn’t life-threatening, after which home treatment may be possible.

Common in:

Common in any age group, gender, and breed.

Symptoms and types:

Dogs may vomit blood on their first vomit, or it may occur after several episodes of vomiting that haven’t included any blood. The amount of blood and color of blood can make a difference to where the blood is coming from and how serious it is, so take a photo for your vet if you can.

Light streaks of blood, especially only occasionally, are generally less serious than red vomit. Dark specks of coffee grounds in the vomit suggest that the blood has been partially digested, and the bleeding may have occurred less recently. 

Other symptoms you should look out for include bloody stools, tarry feces (melena), lack of appetite, and coughing. Pale gums are an indication that the blood loss is severe and is a sign of an emergency.

Even the ‘mild’ cases caused by stomach inflammation do need medical intervention to help dog settle down.

Understanding the diagnostics

Your veterinarian will want to talk to you briefly about your dog’s history, especially any possible toxin exposure, then examine your dog. They’re looking for signs of dehydration, anemia, and any indications as to the possible cause.

Your veterinarian will likely recommend blood tests. Imaging such as an x-ray or ultrasound may be recommended. In an anesthetized dog, a camera called an endoscope can be used to check the esophagus and stomach for foreign objects and ulcers.

Learning about the causes

Dogs may vomit blood for a number of reasons. These can loosely be divided into problems with the stomach and guts (the gastrointestinal system) and other problems that cause blood in the vomit, such as bleeding disorders.

Inflammation

Severe inflammation after irritation from non-food items or consistent vomiting causes blood vessels to burst, leaking blood. The amount of blood produced is usually small and seen as a streak in the bile – it’s rarely an emergency.

Injury to the esophagus, stomach, and guts

The gullet (esophagus), stomach, and guts can all become injured die to parasites, non-food items, or through contact with batteries or caustic chemicals. In addition, the stomach acid can ‘erode’ the lining of the stomach or the esophagus, causing an ulcer. This is more likely in certain diseases or with certain drugs. If the injury is deep enough for stomach contents to leak out of the stomach, the consequences are life-threatening.

Tumors

Tumors of the stomach and guts are often more prone to bleeding than the normal gut wall, so dogs with gastric tumors are more likely to vomit blood. Unless the tumor has caused a hole in the gut wall, this sort of bleed is rarely severe.

Coagulation problems

Dogs that have eaten rat poison, dogs that have been born with coagulation problems, or dogs with liver failure cannot clot their blood properly. Bleeding can happen anywhere in the body including the stomach. Usually, you’ll see more blood than with some of the other types of bleeding – the whole vomitus may be tinged red. Other signs of coagulopathy may be noticed on examination.

Respiratory blood

Sometimes, the blood contained in the vomit has actually been coughed up and swallowed from the lungs, then subsequently vomited. Although unusual, this should be considered in a dog that has been coughing.

Best treatment options

The treatment will depend on the cause.

• For dogs with bloody vomit brought about by an episode of severe vomiting, symptomatic treatment is likely to be effective. This may include anti-nausea medication and fluids to rehydrate them. Dogs with more severe symptoms, or those at risk of ulceration, may need a hospital stay for observation and more intensive treatment.
• For those where a foreign object has caused the bleeding, removal with surgery may be recommended. Some tumors can also be removed with surgery, although many will be better treated with chemotherapy.

Your veterinarian will talk through the best options for treatment depending on your dog’s individual case.

Home remedies and their effectiveness

You shouldn’t try to treat a dog throwing up blood at home, as many causes can be life-threatening.

If your dog has started vomiting blood, it’s best to see a vet. Even the ‘mild’ cases caused by stomach inflammation do need medical intervention to help them settle down. Many causes are more severe and some can be life-threatening, so it’s best to let your vet make that assessment.

However, simple home care when your dog first starts vomiting can prevent them progressing to throwing up blood. Removing food for several hours allows the stomach to settle. You should then re-introduce small amounts of a bland diet little and often so as not to overwhelm your dog’s stomach. This may be enough to stop your dog from vomiting, but if it’s ineffective it’s still recommended to see a vet.

When to see a vet

Most cases of vomiting blood should be assessed by a vet. Dogs vomiting blood is an emergency if:

• They have known exposure to a toxin 
• They may have swallowed a foreign object
• They are unable to keep food or water down
• Their vomit contains significant amounts of blood (more than just a streak)
• They are lethargic or collapsed
• Their gums are pale
• The blood has appeared in more than three piles of vomitus

If your dog is vomiting blood without these signs, they should still be assessed by a vet, but they may be able to wait until morning. It is still recommended that you call and ask your emergency vet’s opinion if you are in any way concerned about your dog.