Why Does Stomach Cancer Cause Vomiting Blood?

Vomiting Blood is a common presentation of Stomach Cancer. The blood may be bright red when bleeding is fresh, or dark and grainy like coffee grounds after stomach acid has changed it. The amount can vary, and even a small amount should not be ignored.

A tumour can make the stomach lining fragile and prone to bleeding. It may also cause an ulcerated area, inflammation, or narrowing that triggers forceful retching. Retching itself can irritate or tear the upper digestive tract, so stomach cancer is not the only possible explanation for blood in vomit. Other causes include stomach ulcers, inflammation, enlarged veins, and medicines that affect clotting.

Doctors assess the colour and amount of blood, other symptoms, medicines, and medical history. Tests may include blood tests and an upper endoscopy, which allows a specialist to inspect the oesophagus and stomach and sometimes treat a bleeding area.

Treat vomiting blood as an urgent symptom. Contact emergency services or go to an emergency department, especially if bleeding is ongoing or you feel faint. Do not drive yourself if you are weak, dizzy, confused, or drowsy. Keep a record or photograph of the vomit if it is safe to do so, and take a list of medicines, including aspirin, anti-inflammatory pain medicines, and blood thinners. Do not eat or drink until a clinician advises you, because an urgent procedure or treatment may be needed.

Seek emergency help immediately for repeated vomiting of blood, black or tar-like stools, severe abdominal pain, fainting, marked weakness, rapid breathing, clammy skin, or confusion. These signs can accompany significant blood loss or shock. If you have a known stomach cancer diagnosis, tell the emergency team and your oncology team; if you are waiting for a diagnosis, explain when the bleeding began and whether the vomit was red or coffee-ground-like.

Ask what may be causing the bleeding, whether you need an endoscopy or blood tests, and which medicines you should pause or continue. Ask how your cancer treatment could affect bleeding, what warning signs should prompt another emergency visit, and who to contact outside clinic hours.