My dog is vomiting blood — what it means and what to do

The short answer

Any visible blood in vomit warrants a vet conversation today. Persistent vomiting of blood, large-volume blood, or coffee-grounds material in a senior or unwell dog is a same-day emergency.

Three kinds of blood

Frank red blood. Bright red, fresh — from the mouth, oesophagus, or upper stomach. Usually visible streaks or small clots. Common after vigorous retching; less common as a marker of significant pathology unless persistent.
Coffee-grounds. Dark brown to black, granular — partially digested blood. Indicates blood that has been in the stomach for hours. More concerning than fresh red, as it suggests larger-volume or longer-standing bleeding.
Tinged or streaked vomit. Pinkish or with small streaks — minor irritation of stomach or oesophageal lining. Less alarming but still warrants attention if recurring.

Five common causes, with rough urgency

Gastric ulceration. Often NSAID-related, sometimes stress, sometimes inflammatory. Treatable with proton-pump inhibitors and stopping the offending agent. Same-day vet visit.
Foreign body. Swallowed object damaging the GI tract. Often presents with persistent vomiting and abdominal pain. Surgical or endoscopic removal. Emergency.
Hemorrhagic gastroenteritis (HGE). Acute, severe vomiting and bloody diarrhoea. Treatable with IV fluids and supportive care. Emergency.
Coagulopathy. Rat-poison ingestion, immune-mediated thrombocytopenia, severe liver disease. Treatable depending on cause; some are emergencies. Often other bleeding (gums, urine, skin) visible.
Gastric or intestinal mass. Cancer (lymphoma, adenocarcinoma, leiomyosarcoma) or benign mass with surface ulceration. Older dogs more affected. Diagnosis often requires endoscopy or imaging.

Other causes include severe parvovirus, pancreatitis, kidney failure (uraemic gastritis), and trauma. The differential is wide; the diagnostic approach is structured.

When this is urgent tonight

Multiple episodes of vomiting blood in 6 hours.
Large-volume blood (more than streaks).
Concurrent lethargy, pale gums, weakness, or collapse.
Bloody stools at the same time.
Known recent NSAID use or human-medication exposure.
Possible foreign-body ingestion (chewed toys, bones, items missing).
Any senior dog or one with known chronic disease.

What the vet will do

Physical exam. Hydration, abdominal palpation, gum colour, capillary refill.
Bloodwork. CBC (anaemia), biochemistry (kidney/liver), coagulation panel.
Imaging. Abdominal radiographs and/or ultrasound — looking for foreign body, mass, free fluid.
Stabilisation. IV fluids, anti-emetic, gastroprotectant (omeprazole, sucralfate), analgesia as appropriate.
Definitive diagnostics. Endoscopy or surgical exploration where indicated.

In a known terminal patient

For a dog with known late-stage cancer, severe gastrointestinal disease, or end-stage kidney failure, the appearance of significant haematemesis sometimes marks the welfare threshold for euthanasia rather than a presentation for further intervention.

The honest conversation with your vet: how realistic is restoration to a comfortable baseline? If the answer is “possibly, with intensive intervention,” that is one path. If the answer is “the underlying disease is now driving the bleeding and intervention is unlikely to hold,” the kindest course may be home euthanasia today or tomorrow.

Common questions

Is a single episode of bloody vomit always an emergency?

Not always — but it is always a clinical signal. A small streak of fresh blood after retching can come from minor oesophageal irritation; persistent or large-volume blood vomiting is a same-day vet visit at minimum.

My dog ate something hours ago and vomited it back with blood — is that food intolerance?

Possibly, especially with new food or rich human-food. Still warrants a vet check if the blood volume is more than a streak, if vomiting recurs, or if the dog seems lethargic or painful.

What are coffee-grounds?

Partially digested blood appears dark brown or black and granular — like coffee grounds. It indicates blood that has been in the stomach for some hours. The most common causes are gastric ulceration, NSAID toxicity, or gastric tumour bleeding.

My senior dog on NSAIDs has bloody vomit — is the medication causing it?

Possibly. NSAID-induced gastric ulceration is a recognised side-effect, particularly in dogs on long-term therapy or in combination with other medications. Stop the NSAID, do not start again without veterinary review, and seek vet attention today.

Editorial reference, not veterinary advice. — Dr. NRS, last reviewed 27 April 2026.