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Last full review/revision Mar 2021| Content last modified Mar 2021
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What is gastritis?

"Gastric" is a word for stomach, and "-itis" means inflammation. So gastritis is inflammation (irritation) of your stomach lining. It can come and go quickly (acute) or last a long time (chronic) depending on the cause.

  • Gastritis may be caused by infection, stress, or medicine

  • You might have pain or discomfort in your belly area, feel sick to your stomach, or throw up blood

  • Doctors may need to look into your stomach with a flexible viewing tube

  • Doctors will give you medicine to lower the amount of acid in your stomach

What causes gastritis?

Common causes of gastritis include:

  • Drinking alcohol or other harsh substances that hurt your stomach lining

  • Infection, most commonly with bacteria called Helicobacter pylori

  • Stress, including stress from serious injury or illness

  • Medicines that irritate your stomach, including certain pain medicines (NSAIDs, such as aspirin or ibuprofen)

What are the symptoms of gastritis?

Gastritis may not cause symptoms.

If you do have symptoms, they can include:

  • Pain or discomfort in your belly, usually in the upper middle part

  • Feeling sick to your stomach or throwing up

If gastritis causes stomach bleeding, you may:

  • Throw up blood or dark material that looks like coffee grounds

  • Pass dark black stool (poop)

How can doctors tell if I have gastritis?

Doctors can often tell if you have gastritis based on your symptoms. Tests usually aren't needed.

Sometimes, doctors may:

  • Look in your stomach with an endoscope (a flexible viewing tube)

  • Do a biopsy (take a sample of your stomach lining to look at under a microscope)

How do doctors treat gastritis?

Doctors treat symptoms with medicines, such as:

  • Antacids, which neutralize the acid in your stomach and are available without a doctor's prescription

  • Acid-reducing medicines, which cause your stomach to make less acid

  • Antibiotics, if your gastritis is from infection with Helicobacter pylori bacteria

Doctors will also have you avoid certain foods and drinks and stop taking medicines that hurt your stomach lining, such as aspirin or other NSAIDs (such as ibuprofen).

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