What causes gastritis?

Helicobacter pylori is a bacterium that can live in the stomach and trigger ongoing irritation. Long-term or heavy alcohol use can weaken the stomach’s protective lining. Anti-inflammatory pain medicines, including ibuprofen and aspirin, may also irritate this lining, especially when used often or at higher doses.

Gastritis can also develop when the immune system mistakenly attacks stomach cells, or during severe physical stress such as a serious illness, major injury or intensive medical treatment. Sometimes several factors are present together, and the exact cause is found only after a clinician reviews your symptoms, medicines and medical history.

Arrange a medical assessment if upper-abdominal discomfort, nausea, vomiting or indigestion keeps returning. A clinician may review your use of pain medicines, ask about alcohol and consider testing for Helicobacter pylori. Do not stop prescribed aspirin or another medicine without advice; the safest change depends on why you take it.

Until you are assessed, avoid alcohol and do not add over-the-counter anti-inflammatory pain medicines unless a healthcare professional says they are suitable. Keep a short record of symptoms, medicines and foods or drinks that seem to worsen discomfort.

Seek urgent medical help for vomiting blood, vomit that looks like coffee grounds, black or tar-like stools, fainting, marked weakness, severe abdominal pain or trouble keeping fluids down. These signs can indicate bleeding or another condition that needs prompt assessment.

You could ask: Could Helicobacter pylori be contributing to my symptoms? Could any of my medicines irritate my stomach? Do I need a test, and which warning signs should prompt urgent help?