Why Is My Cat Vomiting Blood?

Jennifer Coates, DVM
Written by:
Published: August 31, 2022
Why Is My Cat Vomiting Blood?

Most cats vomit from time to time, often because they ate something that didn’t agree with them, or they need to get rid of a hairball.

If your cat vomits once or twice but seems to be fine otherwise, you can keep an eye on them to make sure they don’t have other symptoms or vomit again. But when there’s blood in your cat’s vomit, taking a “wait and see” approach can be dangerous.

Let’s take a look at how blood shows up in cat vomit, when you should go to the emergency vet, and what could be causing this.

What Does Blood in Cat Vomit Look Like?

A lot of bright red blood in cat vomit will certainly get your attention, but sometimes blood can be hard to identify. A small amount may just look like a light red or pink streak along with mucus, water, or other material. Blood clots in vomit are often darker red and look like gelatin.

Blood that has been sitting in the digestive tract for a while can be partially digested when your cat vomits it up. It’s often described as looking a little bit like coffee grounds.

Whatever its appearance, blood in your cat’s vomit usually means that there is a problem in their upper gastrointestinal (GI) tract—specifically the mouth, esophagus, stomach, and the first part of the small intestine. However, cats with respiratory diseases or injuries will sometimes swallow blood that has drained from their nose or has been coughed up, and then they will vomit.

How Serious Is It When a Cat Throws Up Blood?

Vomiting blood is never normal for cats. You should always talk to a veterinarian to determine if this is an emergency situation or if your cat can wait to be seen. Here are some general guidelines to help you determine how urgent the situation might be:

See a veterinarian immediately:

  • Large amounts of blood

  • Severe vomiting

  • Apparent abdominal pain

  • Weakness or lethargy

  • Altered level of awareness

  • Severe diarrhea

  • Won’t eat or drink

  • Any other worrisome symptoms

  • Cat is “high risk,” including kittens, pregnant cats, or cats with underlying health problems

Call a veterinarian for advice:

  • Very small amount of blood

  • Infrequent vomiting

  • Cat appears comfortable

  • Normal activity

  • Bright and alert

  • Mild diarrhea or no change in stool

  • Normal appetite

  • Cat seems to feel okay otherwise

  • Cat is a healthy adult with no underlying health issues

Why Your Cat Is Throwing Up Blood

Cats can throw up blood for many reasons. Here are some of the most common:

  • Chronic Vomiting – This is when cats have a history of vomiting episodes. Chronic vomiting can be caused by many underlying health issues that can irritate the GI tract and cause bleeding.

  • Foreign Body – Cats who swallow bones or anything else that lodges in or damages the mouth, esophagus, stomach, and small intestines may vomit blood.

  • Inflammatory Bowel Disease (IBD) – Severe IBD can damage the lining of the GI tract to the point where it bleeds.

  • Cancer - Benign and especially malignant cancers of the GI tract may damage blood vessels. Sometimes cancer outside the gastrointestinal tract, such as mast cell tumors, can also lead to GI bleeds.

  • Kidney Disease – Cats with kidney disease frequently vomit. The vomit may include blood due to irritation of the lining of the GI tract or ulcers.

  • Bacterial, Viral, and Fungal InfectionsPanleukopenia, salmonellosis, and other infections of the GI tract may damage its lining and cause bleeding.

  • Blood Clotting Disorders – Diseases or poisonings (certain rodenticides, for example) that prevent normal blood clotting can lead to GI bleeding.

  • Drugs and Toxins – Some drugs, like non-steroidal anti-inflammatories (NSAIDs) and corticosteroids, can cause GI ulcers or hinder blood clotting, particularly in cases of overdose. Exposure to some toxins, like caustic cleaning materials, can also cause GI bleeding.

  • Postoperative Complication – Surgery on the gastrointestinal tract can result in GI bleeding and blood in the vomit.

  • Shock – Heat stroke, burns, exposure to an animal’s venom through a bite or sting, severe allergic reactions (anaphylaxis), bleeding, anesthetic complications, severe infections, and anything that leads to very low blood pressure and shock can damage the gastrointestinal tract and cause it to bleed.

  • Brain Injury or Disease – Conditions that increase pressure within the skull can stimulate the vagus nerve, which makes the stomach more acidic and can lead to bleeding GI ulcers.

  • Liver Disease – Liver disease can result in chronic vomiting and sometimes alter the ability of blood to clot.

  • Swallowing Blood – Your cat may have swallowed blood from a nosebleed, oral injury, or respiratory disease, which can cause them to become nauseous and vomit blood.

How Do Vets Diagnose Vomiting Blood in Cats?

To start sorting through the many reasons why a cat could be vomiting blood, a veterinarian will ask a series of questions, such as:

  • Has your cat previously been diagnosed with any health problems?

  • Has your cat had any recent traumatic events or surgeries?

  • Do you give your cat any medications, or could they have gotten into any drugs or toxins?

  • Has your cat eaten anything unusual?

  • Could your cat have gotten into anything outdoors?

  • When did your cat first start vomiting?

  • Did it come on gradually or suddenly?

  • Was blood present when they first vomited, or did you start noticing it later?

  • What other symptoms does your cat have?

Next, the vet will perform a physical examination to look for clues, like an abdominal mass or bruises that might point toward a blood-clotting disorder. Laboratory tests are also usually necessary. These might include a blood chemistry panel, complete blood cell count, specialized laboratory tests, x-rays, an ultrasound exam, endoscopy, surgery, and tissue biopsies.

How Do Vets Treat Cats That Are Vomiting Blood?

Cats that are vomiting a lot of blood may need intravenous fluids or blood transfusions to stabilize their condition. Sometimes endoscopy or surgery may be needed to stop the bleeding.

Then, treatment will focus on the underlying problem. For example, cats that have ingested an anticoagulant rodenticide will be given vitamin K, whereas a bleeding tumor in the intestine will be surgically removed. The vet may also give your cat medications to reduce stomach acid secretions, coat ulcers, or stabilize blood clots.

Always take blood in cat vomit seriously. The sooner your cat gets the treatment they need, the better they’re likely to do.

Featured Image: iStock.com/Evgeniya Pavlova


Help us make PetMD better

Was this article helpful?

Related Articles

Why Is My Cat Lethargic?
Why Is My Cat Lethargic?
Why Is My Cat Drooling?
Why Is My Cat Drooling?
Why Your Cat is Throwing Up and What To Do
Why Your Cat is Throwing Up and What To Do
Connect with a Vet

Subscribe to PetMD's Newsletter

Get practical pet health tips, articles, and insights from our veterinary community delivered weekly to your inbox.