Gastritis

Gastritis means inflammation of the stomach lining. It may develop suddenly, called acute gastritis, or continue for months or years, called chronic gastritis.

The most common important causes are infection with Helicobacter pylori, usually shortened to H. pylori, and autoimmune gastritis. In autoimmune gastritis, the immune system mistakenly attacks healthy cells in the stomach lining.

Medicines such as nonsteroidal anti-inflammatory drugs, including ibuprofen and naproxen, can damage the stomach lining. Alcohol, bile reflux, and severe physical illness can also cause injury. Some of these problems are more accurately called gastropathy, meaning damage with little inflammation, but they are often described as gastritis in everyday use.

Gastritis matters because ongoing inflammation can sometimes cause bleeding, ulcers, low iron or vitamin B12 levels, and lasting changes to the stomach lining. Many people have no symptoms, and symptoms do not always show how much inflammation is present.

Gastritis may cause:

• Aching, burning, or discomfort in the upper abdomen
• Nausea or vomiting
• Feeling full soon after starting a meal
• Reduced appetite
• Bloating or belching

These symptoms are not specific to gastritis. Reflux, indigestion, ulcers, gallbladder conditions, and other digestive problems can feel similar. Symptoms alone cannot confirm that the stomach lining is inflamed.

If the lining bleeds, you may vomit red blood or material that looks like coffee grounds. Digested blood can make stools black, sticky, and tar-like. Slow bleeding may cause iron-deficiency anaemia, which can lead to tiredness, weakness, shortness of breath, or pale skin.

Some people with chronic gastritis have no discomfort and are diagnosed only after blood tests or an examination for another reason.

**H. pylori infection** is a major cause of chronic gastritis. This bacterium can live in the stomach lining for years. It is usually acquired during childhood, although symptoms or complications may not appear until later.

Autoimmune gastritis develops when the immune system attacks acid-producing stomach cells and a protein called intrinsic factor. Intrinsic factor helps the body absorb vitamin B12. The condition can eventually cause vitamin B12 deficiency and pernicious anaemia.

Nonsteroidal anti-inflammatory drugs like ibuprofen or naproxen, or NSAIDs, include medicines such as aspirin, ibuprofen, and naproxen. They can weaken the stomach's protective lining, especially when used regularly. The risk of injury can be higher with older age, previous ulcers, or certain other medicines.

Other possible causes or contributors include:

• Heavy alcohol use
• Bile flowing back into the stomach
• Radiation or some cancer treatments
• Severe burns, major surgery, critical illness, or serious infection
• Less common infections in people with weakened immune systems
• Inflammatory conditions such as Crohn's disease
• Allergic or immune-related inflammation involving eosinophils, a type of white blood cell

Everyday emotional stress does not usually cause stomach inflammation by itself. Severe physical stress during critical illness is different and can cause acute erosive injury.

A healthcare professional will ask about your symptoms, medicine use, alcohol intake, previous ulcers, and family or personal history of autoimmune conditions. An examination may help identify tenderness or signs of anaemia, but it cannot confirm gastritis.

Upper gastrointestinal endoscopy is the main way to look directly at the stomach. A thin, flexible camera is passed through the mouth while you receive medicine to make the procedure more comfortable. Small tissue samples, called biopsies, can be taken. Examining these samples under a microscope confirms inflammation and can show its type and extent.

Tests for H. pylori may include a urea breath test, stool antigen test, or testing of biopsy samples. Some acid-reducing medicines like omeprazole or lansoprazole, antibiotics like amoxicillin or doxycycline, and bismuth products can affect test results, so follow the preparation instructions you receive.

Blood tests may check for anaemia, iron deficiency, vitamin B12 deficiency, or antibodies associated with autoimmune gastritis. These findings support the diagnosis and identify complications, but they do not show the stomach lining directly.

Not everyone with upper abdominal symptoms needs an endoscopy. The choice depends on factors such as bleeding, persistent vomiting, anaemia, weight loss, age, medical history, and response to initial care.

Treatment is based on the cause rather than symptoms alone.

If H. pylori is present, treatment uses a combination of antibiotics and an acid-suppressing medicine. The exact combination is chosen according to local antibiotic resistance, previous antibiotic use, allergies, and other health factors. A breath test, stool test, or sometimes biopsy testing is used afterward to confirm that the infection has cleared.

Proton pump inhibitors reduce stomach acid and allow damaged tissue to heal. Another group, called H2-receptor blockers, also reduces acid. Antacids may briefly ease symptoms but do not treat H. pylori or autoimmune inflammation.

When an NSAID is contributing, a healthcare professional may advise stopping it, reducing exposure, changing medicines, or adding stomach protection. Do not stop prescribed aspirin or another important medicine without discussing it first, particularly if it was prescribed to prevent a heart attack or stroke.

Autoimmune gastritis cannot currently be reversed by suppressing the immune reaction. Management focuses on checking for and replacing vitamin B12 or iron, treating anaemia, and monitoring lasting changes in the stomach lining. Some people need long-term vitamin replacement.

Bleeding, severe erosive injury, or an ulcer may require hospital treatment. Endoscopy can sometimes locate and stop active bleeding.

Food changes can help with comfort, but there is no single diet that cures gastritis. Smaller meals and avoiding foods or drinks that reliably worsen your symptoms may be useful.

Possible complications include stomach ulcers and bleeding. Ongoing blood loss may cause iron-deficiency anaemia.

Autoimmune gastritis can reduce vitamin B12 absorption. Severe or prolonged deficiency may affect the nerves, causing numbness, balance problems, memory changes, or weakness.

Long-standing H. pylori or autoimmune inflammation can lead to atrophy, meaning thinning and loss of normal stomach glands. It may also cause intestinal metaplasia, in which stomach cells change to resemble intestinal cells. These changes raise the risk of stomach cancer and certain stomach neuroendocrine tumours, but most people with gastritis do not develop cancer.

Gastritis cannot always be prevented. There is no established way to prevent autoimmune gastritis.

Good hand hygiene and safe food and water practices may reduce the spread of H. pylori, although exactly how the infection spreads is not fully understood.

Using NSAIDs only as directed and avoiding heavy alcohol use can reduce avoidable stomach injury. If you need long-term aspirin or another NSAID, your personal risks and possible stomach protection should be reviewed rather than changing treatment on your own.

Treating confirmed H. pylori infection helps prevent continued inflammation and lowers the chance of some complications.

Acute irritation may settle after its cause is removed and the stomach lining heals. The timing is different for each person and depends on the cause, severity, and whether bleeding or an ulcer is present.

After successful H. pylori treatment, active inflammation often improves. However, established atrophy or intestinal metaplasia may not fully return to normal. Reinfection after successful treatment is possible but is not the same as treatment failing to clear the original infection.

Autoimmune gastritis is usually lifelong. It may remain quiet for long periods, but vitamin B12 and iron levels can change over time. Follow-up may include blood tests and, for some people, repeat endoscopy based on biopsy findings and individual cancer risk.

Most people can continue their usual activities once symptoms and deficiencies are controlled. Persistent symptoms do not always mean inflammation is worsening, so ongoing discomfort may need assessment for reflux, functional indigestion, or another cause.

Arrange a routine appointment if you have recurring or persistent upper abdominal discomfort, nausea, early fullness, or poor appetite. You should also be assessed if symptoms regularly return after treatment or you frequently need non-prescription acid medicines.

Seek prompt medical care for:

• Repeated vomiting or difficulty keeping fluids down
• Unexplained weight loss
• Trouble or pain when swallowing
• Increasing weakness, breathlessness, or unusual tiredness
• New symptoms while regularly using aspirin or another NSAID
• Known gastritis with worsening or changing symptoms

Seek emergency help for vomiting blood or material resembling coffee grounds. Black, sticky, tar-like stools may also signal bleeding, especially when accompanied by dizziness, fainting, confusion, a fast heartbeat, or shortness of breath.

Iron and bismuth medicines can darken stools, but do not assume they explain black, tarry stools when bleeding is possible.

Is gastritis the same as acid reflux?

No. Gastritis is inflammation of the stomach lining. Acid reflux happens when stomach contents move upward into the oesophagus, the tube connecting the mouth to the stomach. Both can cause burning discomfort, and a person can have both conditions.

How long does gastritis last?

Acute gastritis may improve after a short-term trigger is removed and the lining heals. Chronic gastritis can last for years, particularly when caused by untreated H. pylori or an autoimmune reaction. Symptoms may improve before the underlying inflammation has fully settled.

What foods should I avoid with gastritis?

There is no universal gastritis diet. Spicy, fatty, or acidic foods, caffeine, and alcohol can worsen symptoms for some people, but they do not affect everyone in the same way. Avoiding a food is most useful when it repeatedly triggers symptoms. Very restrictive diets can cause nutritional problems.

Can stress cause gastritis?

Ordinary emotional stress does not usually cause inflammation of the stomach lining. It can increase nausea, indigestion, or pain and may affect eating, alcohol use, or medicine use. Severe physical stress from critical illness, major injury, burns, or surgery can cause acute stomach injury.

Is gastritis contagious?

Gastritis itself is not contagious. However, H. pylori, one of its main causes, can spread between people. Spread may occur through contact with saliva, vomit, or stool, often among people living closely together.

Can gastritis turn into cancer?

Most gastritis does not become cancer. Long-standing H. pylori infection and autoimmune gastritis can cause atrophy and intestinal metaplasia, which increase stomach cancer risk. The level of risk is influenced by the extent of these changes and other personal factors.