Definition of Gastritis:

Gastritis occurs when the lining of the stomach becomes inflamed or swollen.

Gastritis can last for only a short time (acute gastritis), or linger for months to years (chronic gastritis).

Causes, incidence, and risk factors:

The most common causes of gastritis are:

• Certain medications, such as aspirin, ibuprofen, or naproxen, when taken over a longer period of time
• Drinking too much alcohol
• Infection of the stomach with a bacteria called Helicobacter pylori

Less common causes are:

• Autoimmune disorders (such as pernicious anemia)
• Backflow of bile into the stomach (bile reflux)
• Cocaine abuse
• Eating or drinking caustic or corrosive substances (such as poisons)
• Extreme stress
• Viral infection, such as cytomegalovirus and herpes simplex virus, especially in people with a weak immune system

Trauma or a severe, sudden illness such as major surgery, kidney failure, or being placed on a breathing machine may cause gastritis.