A cat throwing up red liquid is vomiting blood, and it nearly always signals a problem that needs veterinary attention. The red color comes from bleeding somewhere along the digestive tract, from the mouth all the way down to the stomach or upper intestines. How the blood looks, bright red versus dark and grainy, tells you a lot about where the bleeding is coming from and how urgent the situation is.
What the Color and Texture Tell You
Not all bloody vomit looks the same, and the differences matter. Bright red blood or pink-streaked liquid means fresh bleeding, typically from the mouth, esophagus, or stomach lining. You might see it mixed with mucus, water, or partially digested food. Blood clots in vomit tend to be darker red, clumpy, and slimy.
If the vomit looks like dark brown coffee grounds rather than bright red, that blood has been sitting in the stomach long enough to be partially digested by stomach acid. This points to a slower, ongoing bleed deeper in the digestive tract. Both presentations warrant a vet visit, but coffee-ground vomit often suggests a more established problem like an ulcer or tumor.
Sometimes the explanation is surprisingly simple: a cat with a nosebleed, a cut inside the mouth, or a respiratory issue can swallow enough blood to trigger nausea and vomit it back up. Check your cat’s mouth and nose for obvious injuries before assuming the worst.
Common Causes of Bloody Vomit in Cats
Stomach Ulcers
Gastrointestinal ulceration is the single most common cause of digestive tract bleeding in cats. An ulcer is essentially an open sore on the stomach or intestinal lining. In cats specifically, ulcers are frequently linked to tumors (including intestinal lymphoma and a type of cancer involving mast cells), but inflammatory bowel disease is also an important non-cancer cause. Liver disease, kidney failure, and pancreatitis can all contribute to ulcer formation as well.
Foreign Objects
Cats are notorious for swallowing things they shouldn’t, and string is the classic culprit. Yarn, thread, tinsel, rubber bands, and fabric strips can wrap around the base of the tongue and trail down into the stomach and intestines. As the gut tries to move the string along, it pulls taut and can slice through the stomach or intestinal wall. Other common foreign bodies include small toys, hair ties, and pieces of plastic. Any of these can scrape or puncture the digestive lining on the way down, producing bloody vomit.
Medications and Toxins
Human pain relievers like ibuprofen, aspirin, and naproxen are extremely dangerous to cats. These drugs damage the protective lining of the stomach, and even a single dose can cause ulceration and bleeding. Corticosteroids carry a similar risk. Never give your cat any over-the-counter medication without veterinary guidance.
Rat and mouse poisons are another serious concern, especially for cats that go outdoors or hunt rodents that have been poisoned. Anticoagulant rodenticides work by blocking the body’s ability to recycle vitamin K, which is essential for blood clotting. Without functional clotting, bleeding can start anywhere in the body, including the digestive tract. The dangerous part is the delay: a cat exposed to rodenticide may seem perfectly fine for two to five days before bleeding symptoms appear. By that point, blood loss can be severe.
Inflammatory Bowel Disease
Chronic inflammation of the stomach or intestinal walls can erode tissue enough to cause bleeding over time. Cats with IBD often have a history of intermittent vomiting, weight loss, and poor appetite before blood ever appears in the vomit.
Infections and Parasites
Hookworms, roundworms, and coccidia can damage the intestinal lining and cause bleeding. Bacterial infections from organisms like Salmonella, Clostridium, and Campylobacter can do the same. Viral infections, including feline parvovirus, are less common but can cause severe gastrointestinal hemorrhage, particularly in unvaccinated kittens.
Signs Your Cat Needs Emergency Care
Any cat vomiting blood should see a vet, but certain signs mean you should go immediately rather than waiting for a regular appointment. Check your cat’s gums: healthy gums are pink and moist. Pale, white, or grayish gums indicate significant blood loss or shock. Press a finger against the gum briefly. In a healthy cat, the color returns within one to two seconds. If it takes longer, blood circulation is compromised.
Other red flags include lethargy or collapse, rapid breathing, a body that feels cold to the touch, refusal to eat or drink, repeated episodes of bloody vomit, or a swollen or painful abdomen. Cats in shock often become unusually quiet and still, with a slow heart rate and low body temperature, which is the opposite of what you’d see in a dog. If your cat shows any combination of these signs alongside bloody vomit, treat it as an emergency.
If you suspect your cat has eaten rat poison, gotten into medication, or swallowed a string or foreign object, don’t wait for symptoms to worsen. Bring the packaging of whatever your cat may have ingested so the vet can identify the specific toxin.
What to Do Before the Vet Visit
Remove food and water temporarily to avoid triggering more vomiting. Keep your cat calm and confined to a small, quiet space. If possible, take a photo of the vomit or bring a sample in a sealed bag. The color, texture, and volume all help your vet narrow down the cause. Note the time of each vomiting episode and whether you’ve seen any other symptoms like diarrhea, loss of appetite, or unusual behavior in recent days.
Do not attempt to induce vomiting or give any home remedies. Do not pull on a string if you see one hanging from your cat’s mouth, as pulling can cause the taut string to slice through intestinal tissue. Leave it for the vet to handle safely.
What Happens at the Vet
Your vet will start with a physical exam and a detailed history: what your cat eats, whether it goes outdoors, what medications or supplements it takes, and when the vomiting started. Blood work is typically the first diagnostic step, checking for signs of anemia, infection, organ dysfunction, and clotting problems. A fecal exam can identify parasites.
If blood work doesn’t reveal a clear answer, imaging is the next step. X-rays and ultrasound can detect foreign objects, masses, intestinal obstructions, and structural abnormalities. Some foreign bodies can be removed with an endoscope, a flexible camera passed down the throat under anesthesia, but many require surgery.
When imaging comes back normal but the cat keeps vomiting blood, a biopsy of the intestinal lining may be needed to check for cancer or inflammatory bowel disease. The diagnostic path depends on what each round of testing reveals, so the process can be quick or involve multiple visits.
Red Liquid That Isn’t Blood
Before assuming the worst, consider whether your cat recently ate something red. Certain wet foods, treats, or dyes in kibble can tint vomit pink or red. If your cat got into beets, tomato sauce, or a red-colored human food, that could explain the color. The texture is the giveaway: food-colored vomit looks uniform, while blood tends to appear as streaks, clots, or the distinctive coffee-ground pattern. If you’re unsure, a vet can test the vomit for the presence of blood.