What causes indigestion (dyspepsia) and how is it treated?

Most people experience indigestion, also known as dyspepsia, at some point in their life. It refers to a collection of symptoms that affect your stomach or upper abdomen. Symptoms include pain, discomfort and/or a burning sensation in your stomach, feeling excessively full after only eating a small amount of food, bloating, nausea and vomiting. 

Indigestion can be caused by a range of underlying conditions but for most people it isn't serious. However, if you experience unintentional weight loss, loss of appetite, repeated vomiting, black or very dark stools or difficulty swallowing (dysphagia), you should see your GP as soon as possible. 

How is indigestion different from GORD and IBS?

Indigestion is not the same as gastroesophageal reflux disease (GORD) or irritable bowel syndrome (IBS), although symptoms can overlap. 

indigestion may be caused by acid in your stomach irritating the upper part of your gut, most often your stomach and the first part of your small intestine (duodenum). 

GORD is caused by acid from your stomach leaking upwards into your gullet (oesophagus), causing heartburn, burping, regurgitation, recurrent coughing, a hoarse voice and chest pain. 

IBS refers to symptoms originating in your small or large intestine, most commonly abdominal pain and cramps, which often occur with changes in your bowel habits, such as diarrhoea or constipation. Other symptoms include an urgency to go to the toilet and a feeling of incomplete emptying of your bowels. 

Getting a diagnosis

If you’re experiencing gut symptoms, your doctor will ask you about them and your medical history. They may need to refer you for tests to rule out certain conditions. Tests may include blood tests, an abdominal ultrasound scan or CT scan and/or a gastroscopy, where a flexible, telescope-like tube with a light and a camera at the end is passed into your stomach via your mouth. 

Your results will determine the type of treatment you have. If you have frequent indigestion but no underlying health condition can be identified, you may be given a diagnosis of functional dyspepsia. 

Causes of indigestion

Indigestion is usually caused by a poor diet ie eating too much fatty, greasy, spicy or highly processed foods and not eating enough fresh fruits, vegetables, lean protein and whole grains. Other factors that can contribute to indigestion include irregular mealtimes and eating habits, drinking too much alcohol, smoking and stress. 

Prolonged use of certain drugs, including non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen, can also cause indigestion as they can damage your stomach lining and cause stomach ulcers. 

Less common causes of indigestion include gallstones, pancreatitis and gastroparesis, where your stomach empties more slowly or in a delayed manner after eating. 

Around 30% of the population has functional dyspepsia, where frequent bouts of indigestion occur with no clear cause. It is thought that a stomach infection with the bacteria Helicobacter pylori (H. pylori) may be a contributing factor. 

Treating indigestion

Treatment of your indigestion will depend on the underlying cause. Common treatments include taking medication to suppress the amount of acid produced by your stomach eg antacids, H2 receptor antagonists and proton pump inhibitors (PPIs), modifying your diet and lifestyle, and eradicating H. pylori if this is found to be present.

Your doctor or a dietitian may also provide dietary advice to reduce your symptoms and support your gut microbiome ie the balance of bacteria that live in your gut to aid digestion.

If the cause of your indigestion is gastroparesis, which is more common if you have diabetes, your doctor will recommend getting your blood sugar levels under better control and eating smaller, more frequent meals that are low in fat and fibre. You may also be prescribed prokinetics, drugs that help the stomach empty.

Research continues into how best to treat dyspepsia, with newer types of prokinetics in clinical trials and studies investigating the interaction between the immune system and nervous system with the gut. Research is also growing our understanding of the wider effects of dyspepsia on sleep and general quality of life. Together this will help develop better treatment plans.