A peptic ulcer is an open sore that develops in the lining of the digestive tract, most commonly in the stomach or the upper part of the small intestine (the duodenum), and occasionally in the lower part of the oesophagus. Peptic ulcers form when the digestive tract's protective mucous lining is broken down or weakened, allowing stomach acid and digestive enzymes to erode the underlying tissue.
Peptic ulcers are very common and, for most people, highly treatable once identified. The two leading causes — infection with the bacterium Helicobacter pylori (H. pylori) and regular use of certain painkillers — are both well understood, and effective treatments exist for each.
However, if left untreated, peptic ulcers can lead to more serious complications, including internal bleeding, a hole (perforation) in the stomach or intestinal wall, or a blockage in the digestive tract — which is why accurate diagnosis and appropriate treatment matter, even when symptoms seem mild or intermittent at first.
Types of Peptic Ulcers
Peptic ulcers are classified according to where in the digestive tract they occur, which can influence the pattern of symptoms experienced.
- Gastric Ulcer: Develops on the inside lining of the stomach. Pain from a gastric ulcer often occurs shortly after eating, as food entering the stomach stimulates acid production that irritates the already-damaged lining.
- Duodenal Ulcer: The more common type, forming in the duodenum, the first part of the small intestine just beyond the stomach. Pain from a duodenal ulcer often improves temporarily after eating, as food helps neutralise stomach acid, but tends to return two to three hours later or during the night, once the stomach has emptied.
- Oesophageal Ulcer: A less common type that develops in the lower part of the oesophagus, often related to acid reflux disease damaging the oesophageal lining over time.
How Peptic Ulcers Develop
The stomach and duodenum are normally protected from the digestive tract's own acid and enzymes by a thick layer of protective mucus. A peptic ulcer develops when this natural balance is disrupted:
- Breakdown of the protective mucous layer: H. pylori infection, certain medications, or other factors can thin or weaken the mucous lining that normally shields the stomach and duodenum from acid.
- Excess acid production: In some cases, the stomach produces more acid than usual, overwhelming the protective lining even where mucus production is otherwise normal.
- Acid erosion of tissue: Once the protective barrier is compromised, stomach acid and digestive enzymes begin to erode the underlying tissue, forming an open sore, or ulcer.
- Ongoing irritation: If the underlying cause — such as H. pylori infection or continued use of an irritating medication — is not addressed, the ulcer can persist, deepen, or fail to heal, increasing the risk of complications.
Symptoms of Peptic Ulcers
The most common symptom of a peptic ulcer is a dull, burning or gnawing pain in the upper abdomen, though the pattern can vary depending on the type and location of the ulcer. Other common symptoms include:
- Bloating
- Fatigue
- Indigestion
- Nausea and vomiting
- Heartburn
- Belching
- A feeling of fullness, or discomfort after eating even small amounts
Some peptic ulcers cause no symptoms at all and are only discovered when a complication occurs. If an ulcer bleeds, it can cause more serious symptoms that require urgent attention, including vomiting blood (which may appear bright red or resemble coffee grounds), passing dark, tarry or black stools, and feeling dizzy, faint or short of breath as a result of blood loss.
What Causes Peptic Ulcers
Peptic ulcers happen when acid in the digestive tract erodes the inner lining of the stomach or duodenum faster than the body's protective mucous layer can withstand. The two leading causes are:
- Helicobacter pylori (H. pylori) infection: This common bacterium lives in the mucous lining of the stomach and small intestine and often causes no problems at all. In some people, however, it triggers inflammation and weakens the protective lining, allowing an ulcer to form. H. pylori is thought to be responsible for the majority of peptic ulcers worldwide.
- Regular use of certain painkillers: Non-steroidal anti-inflammatory drugs (NSAIDs), including common over-the-counter pain relievers, can irritate and weaken the stomach and duodenal lining with regular or prolonged use, particularly at higher doses or in combination with other risk factors.
Less commonly, peptic ulcers can result from excess acid production due to rare hormone-secreting tumours (Zollinger-Ellison syndrome), or can develop as stress ulcers in people who are critically ill or have suffered severe physical trauma.
Risk Factors for Peptic Ulcers
While H. pylori infection and NSAID use are the leading causes of peptic ulcers, several other factors can increase the likelihood of developing one or make an existing ulcer harder to heal:
- Smoking: Increases the risk of developing peptic ulcers, may worsen existing ulcers, and can slow healing after treatment.
- Alcohol consumption: Regular or heavy alcohol use can irritate and erode the mucous lining of the stomach, and may worsen the effects of H. pylori infection.
- Combining NSAIDs with other medications: Taking NSAIDs alongside corticosteroids, certain antidepressants, or blood-thinning medications further increases the risk of ulcer formation and bleeding.
- Older age: Older adults are more susceptible to peptic ulcers and their complications, partly due to more frequent NSAID use and age-related changes in the digestive tract lining.
- Untreated stress and poor sleep: While stress alone does not directly cause ulcers, it may worsen symptoms and could play a contributing role alongside other risk factors.
- Family history: A family history of peptic ulcers may indicate a higher susceptibility to H. pylori-related complications or shared lifestyle risk factors.
Possible Complications of Peptic Ulcers
Peptic ulcers are usually straightforward to treat, but if left untreated, or if treatment is delayed, they can lead to serious complications:
- Internal bleeding: An ulcer can erode into a blood vessel, causing bleeding that ranges from slow, chronic blood loss (which can lead to anaemia) to sudden, severe bleeding that requires emergency treatment.
- Perforation: In severe cases, an ulcer can erode completely through the wall of the stomach or duodenum, creating a hole that allows digestive contents to leak into the abdominal cavity — a surgical emergency requiring immediate treatment.
- Gastric outlet obstruction: Swelling and scarring from a chronic or recurrent ulcer, particularly near the outlet of the stomach, can narrow or block the passage of food into the small intestine, causing persistent vomiting and an inability to eat normally.
- Peritonitis: If a perforated ulcer allows digestive contents to leak into the abdominal cavity, it can cause a severe, potentially life-threatening infection and inflammation of the abdominal lining.
- Increased stomach cancer risk: Long-standing H. pylori infection, particularly if untreated over many years, is associated with a higher risk of stomach cancer, which is one of the reasons prompt treatment of H. pylori-related ulcers is recommended.
How Peptic Ulcers Are Diagnosed
If a peptic ulcer is suspected based on your symptoms, several tests may be used to confirm the diagnosis, identify the underlying cause, and check for any complications.
- Endoscopy: A thin, flexible tube with a camera is passed through the mouth to directly examine the lining of the oesophagus, stomach and duodenum, allowing an ulcer to be visualised and, if needed, a tissue sample (biopsy) to be taken.
- H. pylori Testing: Can be performed via a breath test, a stool sample test, a blood test, or a biopsy taken during endoscopy, to determine whether H. pylori infection is present and contributing to the ulcer.
- Barium Test: A chalky liquid (barium) is swallowed and tracked using X-ray imaging as it passes through the oesophagus, stomach and duodenum, helping to identify structural abnormalities such as an ulcer.
- Blood Tests: May be used to check for anaemia in cases of chronic or ongoing bleeding, and can support the diagnosis alongside other tests.
Living With a Peptic Ulcer: Diet and Lifestyle
While diet does not cause peptic ulcers, certain foods and habits can aggravate symptoms while an ulcer is healing, and some simple adjustments can support your recovery alongside medical treatment.
Spicy, acidic, or fatty foods, caffeine, and carbonated drinks can worsen symptoms in some people, so it may help to notice and limit foods that seem to trigger discomfort for you personally. Eating smaller, more frequent meals rather than large meals can reduce the amount of acid released at any one time, and avoiding eating close to bedtime may reduce night-time symptoms.
Completing the full course of any prescribed antibiotics and acid-reducing medication, even once symptoms improve, is essential to fully heal the ulcer and prevent recurrence — stopping treatment early is one of the most common reasons ulcers fail to heal completely or return. Managing stress through regular exercise, adequate sleep, and relaxation techniques may also help reduce symptom flares, even though stress alone does not cause ulcers.
How to Prevent Peptic Ulcers
Several measures can help reduce your risk of developing a peptic ulcer, or help prevent one from recurring:
- Take care when using pain relievers: If you regularly use NSAIDs, take them with food, use the lowest effective dose for the shortest necessary duration, and speak to your doctor about whether a protective medication is advisable alongside long-term use.
- Get tested and treated for H. pylori if indicated: If you have a history of peptic ulcers or a family history of H. pylori-related conditions, discuss testing with your doctor, as treating the infection significantly reduces the risk of future ulcers.
- Quit smoking: Smoking increases the risk of peptic ulcers and can slow healing; your healthcare professional can help you access support to quit.
- Limit alcohol consumption: Reducing alcohol intake helps protect the stomach lining and supports overall digestive health.
- Manage stress: While not a direct cause, managing stress through healthy coping strategies may help reduce symptom flares and support overall digestive wellbeing.
- Seek prompt treatment for digestive symptoms: Addressing persistent indigestion, heartburn or stomach discomfort early can help identify and treat an ulcer before complications develop.
