Causes - Stomach ulcer

The causes of stomach ulcers are usually:

  • Helicobacter pylori (H. pylori) bacteria
  • non-steroidal anti-inflammatory drugs (NSAIDs)

These can break down the stomach's defence against the acid it makes to digest food. The stomach lining can get damaged and an ulcer forms.

H. pylori bacteria

H. pylori infections are common. You can have this infection without knowing it as the infection does not usually cause symptoms.

H. pylori bacteria live in the stomach lining. The bacteria can irritate the stomach lining in some people and make it more vulnerable to damage from stomach acid.

It's not clear why some people are more vulnerable to H. pylori bacteria than others. People of all ages can become infected.

Non-steroidal anti-inflammatory drugs (NSAIDs)

NSAIDs are medicines used to treat pain, a fever (high temperature of 38 degrees Celsius or above) or inflammation (swelling).

NSAIDs include:

  • ibuprofen
  • aspirin
  • naproxen
  • diclofenac

Many people take NSAIDs without having any side effects. But there's always a risk of problems, such as stomach ulcers. Problems happen more often if you take NSAIDs for a long time or at high doses.

Your GP may tell you not to use NSAIDs if you have a stomach ulcer or have had one in the past.

You can often use paracetamol instead.

Lifestyle factors

Eating spicy foods, stress and drinking alcohol are not causes of stomach ulcers. But they may make the symptoms of ulcers worse.

Smoking increases your risk of developing stomach ulcers. It may also make treatment less effective.

Read more about stopping smoking


Content supplied by the NHS and adapted for Ireland by the HSE

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This project has received funding from the Government of Ireland’s Sláintecare Integration Fund 2019 under Grant Agreement Number 123.

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