The most common symptom of a stomach ulcer is a burning or gnawing pain that develops in your abdomen (tummy).

But some stomach ulcers aren't painful and are only noticed when a complication of a stomach ulcer develops, such as bleeding from the ulcer.

Tummy pain

The pain caused by a stomach ulcer can travel out from the middle of your tummy up to your neck, down to your belly button, or through to your back.

It can last from a few minutes to a few hours, and often starts within a few hours of eating. You may also wake up in pain during the night.

Taking indigestion medication (antacids) may relieve the pain temporarily, but it'll keep coming back if the ulcer isn't treated.

Other symptoms

Less common symptoms of a stomach ulcer can include:

• indigestion
• heartburn
• loss of appetite
• feeling and being sick
• weight loss

Some people also find they burp or become bloated after eating fatty foods.

When to seek medical advice

Visit your GP if you experience persistent symptoms of a stomach ulcer.

Contact your GP or NHS 111 immediately, or go to your nearest accident and emergency (A&E) department, if you develop signs of a serious complication.

These include:

• vomiting blood – the blood can appear bright red or have a dark brown, grainy appearance, similar to coffee grounds
• passing dark, sticky, tar-like stools
• a sudden, sharp pain in your tummy that gets steadily worse

If you're not sure that you have a stomach ulcer, see other causes of stomach pain.

Stomach ulcers are usually caused by Helicobacter pylori (H. pylori) bacteria or non-steroidal anti-inflammatory drugs (NSAIDs).

These can break down the stomach's defence against the acid it produces to digest food, allowing the stomach lining to become damaged and an ulcer to form.

H. pylori bacteria

H. pylori infections are common, and it's possible to be infected without realising it because the infection doesn't usually cause symptoms. 

The bacteria live in the stomach lining, and people of all ages can be infected.

But in some people, the bacteria can irritate the stomach lining and make it more vulnerable to damage from the stomach acid.

It's not clear exactly why some people are more vulnerable to the effects of H. pylori bacteria than others.

NSAIDs

NSAIDs are medicines widely used to treat pain, a high temperature (fever) and inflammation (swelling).

Commonly used NSAIDs include:

• ibuprofen
• aspirin
• naproxen
• diclofenac

Many people take NSAIDs without having any side effects, but there's always a risk the medication could cause problems, such as stomach ulcers, particularly if taken for a long time or at high doses.

You may be advised not to use NSAIDs if you currently have a stomach ulcer or if you have had one in the past. 

Paracetamol can often be used as an alternative painkiller, as it's generally considered safer.

Lifestyle factors

It used to be thought that stomach ulcers may be caused by certain lifestyle factors, such as spicy foods, stress and alcohol.

There's little hard evidence to confirm that this is the case, but these factors may make the symptoms of ulcers worse.

But it's thought that smoking increases your risk of developing stomach ulcers and may make treatment less effective.

Your GP may suspect you have an ulcer based on your symptoms. They'll want to know if you're taking non-steroidal anti-inflammatory drugs (NSAIDs) and may test you for an Helicobacter pylori (H. pylori) infection.

You may be referred to hospital for a procedure to look inside your stomach called a gastroscopy.

Testing for H. pylori infection

If your GP thinks your symptoms may be caused by an H. pylori infection, they may recommend one of the following tests:

• a urea breath test – you'll be given a special drink containing a chemical that's broken down by H. pylori; your breath is then analysed to see whether or not you have an H. pylori infection
• a stool antigen test – a small stool sample is tested for the bacteria
• a blood test – a sample of your blood is tested for antibodies to the H. pylori bacteria (antibodies are proteins produced naturally in your blood and help to fight infection); this has now largely been replaced by the stool antigen test

If you test positive for H. pylori, you'll need treatment to clear the infection, which can heal the ulcer and prevent it returning.

Read more about treating stomach ulcers.

Gastroscopy

In some cases, you may be referred for a gastroscopy to look inside your stomach directly and see whether you have a stomach ulcer.

The procedure is carried out in hospital and involves passing a thin, flexible tube (an endoscope) with a camera at one end into your mouth and down into your stomach and the first section of the small intestine (duodenum).

You may be given a mild sedative injection before the procedure and have your throat sprayed with a local anaesthetic to make it more comfortable to pass the endoscope.

The images taken by the camera will usually confirm or rule out an ulcer. A small tissue sample may also be taken from your stomach or duodenum so it can be tested for the H. pylori bacteria.

A gastroscopy is usually carried out as an outpatient procedure, which means you won't have to spend the night in hospital.

Read more about what happens during a gastroscopy.

If you have a stomach ulcer, your treatment will depend on what caused it. With treatment, most ulcers heal in a month or two.

If your stomach ulcer is caused by a Helicobacter pylori (H. pylori) bacterial infection, a course of antibiotics and a medication called a proton pump inhibitor (PPI) is recommended.

This is also recommended if it's thought your stomach ulcer is caused by a combination of an H. pylori infection and non-steroidal anti-inflammatory drugs (NSAIDs).

If your stomach ulcer is just caused by taking NSAIDs, a course of PPI medication is recommended.

Your use of NSAIDs will also be reviewed, and taking an alternative painkiller may be advised.

An alternative type of medication, known as H2-receptor antagonists, is occasionally used instead of PPIs.

Sometimes you may be given additional medication called antacids to relieve your symptoms in the short term.

You may have a repeat gastroscopy after 4 to 6 weeks to check that the ulcer has healed.

There aren't any special lifestyle measures you need to take during treatment, but avoiding stress, alcohol, spicy foods and smoking may reduce your symptoms while your ulcer heals.

Antibiotics

If you have an H. pylori infection, you'll usually be prescribed a course of 2 antibiotics, which each need to be taken twice a day for a week.

The antibiotics most commonly used are amoxicillin, clarithromycin and metronidazole.

The side effects of these antibiotics are usually mild and can include:

• feeling and being sick
• diarrhoea
• a metallic taste in your mouth

You'll be retested at least 4 weeks after finishing your antibiotic course has been completed to see whether there are any H. pylori bacteria left in your stomach.

If there are, a further course of eradication therapy using different antibiotics may be given.

Proton pump inhibitors (PPIs)

PPIs work by reducing the amount of acid your stomach produces, preventing further damage to the ulcer as it heals naturally. They're usually prescribed for 4 to 8 weeks.

Omeprazole, pantoprazole and lansoprazole are the PPIs most commonly used to treat stomach ulcers.

Side effects of these are usually mild, but can include:

• headaches
• diarrhoea or constipation 
• feeling sick
• tummy (abdominal) pain
• dizziness
• rashes

These should pass once treatment has been completed.

H2-receptor antagonists

Like PPIs, H2-receptor antagonists work by reducing the amount of acid your stomach produces.

Ranitidine is the most widely used H2-receptor antagonist for treating stomach ulcers.

Side effects are uncommon, but may include:

• diarrhoea
• headaches
• dizziness
• rashes
• tiredness

Antacids and alginates

All of the above treatments can take several hours before they start to work, so your GP may recommend taking additional antacid medication to neutralise your stomach acid and provide immediate, but short-term, symptom relief.

Some antacids also contain a medicine called an alginate, which produces a protective coating on the lining of your stomach.

These medications are available to buy over the counter at pharmacies. Your pharmacist can advise on which is most suitable for you.

Antacids should be taken when you experience symptoms or when you expect them, such as after meals or at bedtime.

Antacids containing alginates are best taken after meals.

Side effects of both medications are usually minor and can include:

• diarrhoea or constipation
• wind (flatulence)
• stomach cramps
• feeling and being sick

Reviewing NSAID use

If your stomach ulcer has been caused by taking NSAIDs, your GP will want to review your use of them.

You may be advised to use an alternative painkiller not associated with stomach ulcers, such as paracetamol.

Sometimes an alternative type of NSAID that's less likely to cause stomach ulcers, called a COX-2 inhibitor, may be recommended.

If you're taking low-dose aspirin (an NSAID) to reduce your risk of blood clots, your GP will tell you whether you need to continue taking it.

If you do need to keep taking it, long-term treatment with a PPI or H2-receptor antagonist may be prescribed alongside the aspirin to try to prevent further ulcers.

It's important to understand the potential risks associated with continued NSAID use.

You're more likely to develop another stomach ulcer and could experience a serious complication, such as internal bleeding.

Complications of stomach ulcers are relatively uncommon, but they can be very serious if they do occur.

Internal bleeding

Internal bleeding is the most common complication of stomach ulcers. It can occur when an ulcer develops at the site of a blood vessel.

The bleeding can either be:

• slow, long-term bleeding, leading to anaemia – causing fatigue, breathlessness, pale skin and heart palpitations (noticeable heartbeats)
• rapid and severe bleeding – causing you to vomit blood or pass stools that are black, sticky and tar-like

You should visit your GP if you have persistent symptoms of anaemia. If they think you may have a stomach ulcer, they may refer you to a gastroenterologist for an examination and treatment.

Contact your GP or NHS 111 immediately, or go to your nearest accident and emergency (A&E) department, if you have symptoms of more severe bleeding.

An endoscopy will be used to identify the cause of the bleeding and treatment can be given during the endoscopy to stop the bleeding.

Sometimes specialised procedures carried out under X-ray guidance are used to stop bleeding ulcers, although surgery may occasionally be required to repair the affected blood vessel.

Blood transfusions may also be needed to replace the blood you have lost.

Perforation

A rarer complication of stomach ulcers is the lining of the stomach splitting open, known as perforation.

This can be very serious because it enables the bacteria that live in your stomach to escape and infect the lining of your abdomen (peritoneum). This is known as peritonitis.

In peritonitis, an infection can rapidly spread into the blood (sepsis) before spreading to other organs. This carries the risk of multiple organ failure and can be fatal if left untreated.

The most common symptom of peritonitis is sudden abdominal pain that gets steadily worse. 

If you have this type of pain, contact your GP immediately. If this isn't possible, call NHS 111 or your local out-of-hours service.

Peritonitis is a medical emergency that requires hospital admission. In some cases, surgery may be needed.

Read more about treating peritonitis.

Gastric outlet obstruction

In some cases, an inflamed (swollen) or scarred stomach ulcer can obstruct the normal passage of food through your digestive system. This is known as gastric outlet obstruction.

Symptoms can include:

• repeated episodes of vomiting, with large amounts of vomit that contain undigested food
• a persistent feeling of bloating or fullness
• feeling very full after eating less food than usual
• unexplained weight loss

An endoscopy can be used to confirm the obstruction. If the obstruction is caused by inflammation, proton pump inhibitors (PPIs) or H2-receptor antagonists can be used to reduce stomach acid levels until the swelling goes down.

If the obstruction is caused by scar tissue, surgery may be needed to treat it, although it can sometimes be treated by passing a small balloon through an endoscope and inflating it to widen the site of the obstruction.