Gastritis means stomach inflammation gastr (stomach) itis (inflammation.) It is a condition where the lining of the stomach becomes inflamed and can be either acute (recent onset) or chronic (long-term.) This is not the same as gastroenteritis, which refers to inflammation in the bowels.

Gastritis is not uncommon; it is reported that more than half the world’s population has chronic gastritis, especially in developing countries. Normally the mucus lining the stomach protects it from the action of digestive juices such as stomach acid and bile. Bile is a digestive secretion produced by the liver and helps fat digestion. Gastritis occurs when this protection is weakened and the digestive juices cause inflammation to occur.


Bacterial infection

Helicobacter pylori infection is the most common cause of gastritis worldwide, and it can cause both short- and long-term gastritis (acute and chronic gastritis). Other microbes such as Herpes simplex and Cytomegalovirus can also cause gastritis, but this is much less frequent. Helicobacter pylori related gastritis is more commonly diagnosed in men.


Some medicines can cause gastritis, and this type of gastritis is common with people taking certain non-steroidal anti-inflammatory drugs for pain relief (NSAIDS). Examples of such anti-inflammatory medicines include ibuprofen, naproxen, diclofenac or aspirin. Please do not stop taking any of these medications without discussing this with your doctor first.


Lifestyle factors can also be a cause of gastritis, typically excessive alcohol intake above the recommended guidelines, recreational drug use and smoking cigarettes.

Bile reflux gastritis

Some compounds produced by the body can also cause gastritis. An example includes the reflux of bile, a substance that is produced by the liver to help the digestion of dietary fats.

The types of gastritis described below are rarer.

Autoimmune gastritis

Autoimmune atrophic gastritis is inflammation in the stomach caused by the body’s cells attacking its own tissues. Cells called parietal cells produce a protein called intrinsic factor, which helps the digestive system absorb (take in) vitamin B12, from food. This factor is destroyed in some people with gastritis.  Lack of this factor results in vitamin B12 deficiency, a condition called pernicious anaemia. This type of gastritis occurs more often in people who have other auto-immune diseases for example auto-immune thyroid disease, diabetes and coeliac disease.

Autoimmune gastritis is underrecognized. It is more common in women and the elderly, and it is estimated that 5 to 20 people out of every 1,000 in the general population suffer from it. Initially, it was presumed to be more prevalent in people of European descent. However, the anaemia that occurs with autoimmune gastritis is more common in people of African American and Hispanic ethnicity in the USA. Autoimmune gastritis often occurs at an earlier age in people of African American and Hispanic ethnicity.

Lymphocytic gastritis

Lymphocytic gastritis is a type of inflammation caused by cells called lymphocytes (a type of white blood cell) in the stomach lining. This gastritis rarely can be caused by Helicobacter pylori infection. However, it has also been found in people who have a negative test for Helicobacter pylori too. This type of inflammation has been found in one out of every ten people with coeliac disease.

Eosinophilic gastritis

Eosinophilic gastritis is a rare type of inflammation of the stomach caused by infiltration of the stomach lining by cells called eosinophils. Eosinophils are a type of white blood cell. This is a rare condition that is believed to occur because of a type of allergic reaction to food, called a non-IgE allergy.

Medical stress

Gastritis can occasionally happen in people that are very unwell and experiencing medical stress. People in the intensive care unit (ICU) are one example. The cause of this type of gastritis is unknown but is suspected to be because of reduced blood flow to the stomach.


Certain types of gastritis can run in the same family.


The symptoms of gastritis can vary from one person to the next. Some people may not have any symptoms and are found to have it on investigation for other symptoms.

Common symptoms are:

  • Indigestion.
  • Feeling sick and being sick.
  • Feeling full after eating.
  • Stomach pain often described as “burning” or “gnawing”.
  • Very rarely, severe gastritis can cause bleeding, which may cause the stool to turn black (called melaena.)

If indigestion lasts longer than three weeks and any of the following are noticed:

  • Changing lifestyle factors has not been effective.
  • Symptoms are severe.
  • You have noticed blood in your poo or vomit.

You should see your GP. Do not continue to treat indigestion with over-the-counter medicines without talking to your doctor.

Do not assume your symptoms are caused by gastritis, the symptoms can be caused by several other conditions.

Headshot of a young man looking at the camera and smiling.


Breath or poo test: If your GP suspects that you might have a Helicobacter pylori infection you may be asked to undergo a breath or stool (poo) test to diagnose it.

Endoscopy (gastroscopy): Gastritis is a pathological diagnosis (made by examining a small piece of the stomach lining under the microscope, called a biopsy). But looking at the lining of the stomach through an endoscope can raise the suspicion of gastritis. An endoscopy is a camera examination using a thin, flexible tube. The tube is passed through the mouth and down into your oesophagus (gullet), stomach and the beginning of the small intestine. A biopsy can be taken for several different tests to check whether gastritis is present. An endoscopy is usually carried out as an outpatient and takes less than 15 minutes. You can choose to have a local anaesthetic throat spray and/or sedative. The endoscopist can guide you in making this decision. The procedure is not painful but may be uncomfortable at times.

Barium swallow and X-ray: this is another test that can identify any abnormalities and may be offered if people are unable to have an endoscopy. The barium coats the surface of the stomach and can highlight any abnormality. This test is less sensitive and specific than an endoscopy to diagnose gastritis.

A female doctor sits at her desk and chats to a male patient while looking at his test results on her digital tablet . She is a blue shirt with the sleeves rolled up and a stethoscope around her neck.


What treatment is available for gastritis?

Lifestyle changes that can help to treat gastritis include stopping smoking, stopping recreational drug use and reducing alcohol intake. These changes can be difficult to make alone, but there is help available from your GP. People who have help are often more successful. Contact your GP to ask about the services available to you.

If the gastritis has been caused by a medicine, ask your doctor or pharmacist if there are suitable alternatives for you to try.


Altering your diet doesn’t generally treat the inflammation. Reducing intake of spicy foods, caffeine containing foods and drinks, fizzy drinks and fried foods might reduce symptoms of indigestion, whilst your medical treatment is working. Eating smaller meals more frequently can prevent weight loss and might be better tolerated if this is a problem. An exception to this is that eosinophilic gastritis may be treated with diet, you should be referred to a state registered dietitian if eosinophilic gastritis is diagnosed. For eosinophilic gastritis, please do not attempt to change your diet without professional advice.


Treatment will be discussed with your doctor, who may advise one or more of the following medicines:

Antacids: These medicines are either liquids or tablets that neutralise (reduce) the amount of acid produced by the stomach.

Alginates: These are products that form a thick protective layer on top of the stomach contents and help reduce reflux symptoms. These can be useful to take after meals and before going to bed to reduce night-time symptoms. Some medications are a combination of both antacids and alginates.

Acid supressing medications: capsules or tablets that reduce the amount of acid produced by the cells in your stomach.

These are split into two groups:

  • Histamine H2-receptor antagonists (H2 blockers). These include, Cimetidine, Famotidine and Nizatidine. These can be taken either during the day or prior to bedtime.
  • Proton pump inhibitors (PPIs). These include omeprazole, lansoprazole, pantoprazole, rabeprazole and esomeprazole. These are best taken 30 minutes prior to a breakfast or evening meal.

Antibiotics: You might be given antibiotics if the gastritis has been caused by an infection. For Helicobacter pylori the usual treatment is triple therapy using two antibiotics and a proton pump inhibitor. The treatment will treat both the Helicobacter pylori infection and the gastritis. It is important that the full course of antibiotics is taken as your doctor advises.

Sucralfate: Sucralfate is a complex of aluminium hydroxide and sulfated sugar. Sulcafrate forms a barrier to protect the stomach lining from acid, pepsin (a digestive enzyme produced in the stomach) and bile reflux.

Anti-sickness medicines: These can be prescribed for symptoms of nausea (sickness).

How will I be monitored over time?

Most people will recover from gastritis with treatment, but others will unfortunately continue to experience symptoms of gastritis and continuing inflammation, this is called chronic gastritis. If medicines such as PPI’s are needed longer term you may be monitored by your GP.

What are the complications of gastritis?

People who have been diagnosed with autoimmune atrophic gastritis or have a long-term Helicobacter pylori infection can have a small risk of developing stomach cancer in the future. People diagnosed with autoimmune atrophic gastritis also have a risk of developing a type of tumour called carcinoid or a neuroendocrine tumour (NET). It must be remembered that most people will not develop cancer. However, if you have symptoms such as being sick, difficulty swallowing, weight loss, pain, blood in poo, reflux or dyspepsia you should contact your GP.

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  • What treatment is best for me?
  • What type of gastritis do I have?
  • Will I need monitoring in the future?


Guts UK is proud to be funding Dr Marnix Jansen’s stomach cancer research. Dr Jansen’s research has the capacity to add to our knowledge of stomach cancer, by exploring the methods used to take biopsies of the stomach but also exploring the DNA changes that occur. Guts UK’s research has the capacity to save lives. Read more here.

References are available on request, please email info@gutscharity.org.uk


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