Blood in stool and vomit: what to know

Vomited blood may be bright red or resemble dark coffee grounds. Black, sticky stool can occur when blood has been altered during passage through the upper digestive tract; bright red blood is often seen nearer the end of the bowel. These patterns are clues rather than a diagnosis.

Possible causes include irritation after forceful retching, ulcers, inflammation, diverticular disease, inflammatory bowel disease, bowel polyps, and other digestive conditions. The presence of blood does not by itself identify cancer, and the amount seen does not reliably show how serious the bleeding is.

Get urgent medical advice and report exactly whether blood was vomited, passed in stool, or both. Do not eat or drink large amounts while actively vomiting. If vomiting has stopped, small sips may help, but avoid alcohol and anti-inflammatory pain medicines unless prescribed for this situation.

Keep the packaging or names of your medicines, especially anticoagulants, aspirin, and steroids. Note the timing, colour, clots, abdominal pain, bowel changes, dizziness, and whether you have had previous ulcers or digestive bleeding. A clinician may assess circulation and hydration and arrange blood tests or digestive investigations.

Call emergency services for vomiting blood repeatedly, black tar-like stool, a large amount of fresh blood, fainting, severe dizziness, confusion, pale or clammy skin, rapid breathing, severe abdominal pain, or inability to keep fluids down. Do not drive if you feel faint.

Ask where the bleeding may be located, whether your medicines need review, which tests are planned, how to manage fluids, and which symptoms mean you should return immediately.