Functional (Non-Ulcer) Dyspepsia

Understanding digestion

Food passes down the oesophagus (gullet) into the stomach. The stomach makes acid which is not essential, but helps to digest food. After being mixed in the stomach, food passes into the duodenum (the first part of the small intestine).

In the duodenum and the rest of the small intestine, food mixes with enzymes (chemicals). The enzymes come from the pancreas and from cells lining the intestine. The enzymes break down (digest) the food. Digested food is then absorbed into the body from the small intestine.

What is dyspepsia?

Dyspepsia (indigestion) is a term which includes a group of symptoms that come from a problem in your upper gut. The gut or 'gastrointestinal tract' is the tube that starts at the mouth, and ends at the anus. The upper gut includes the oesophagus, stomach, and duodenum. Various conditions can cause dyspepsia.

The main symptom of dyspepsia is usually pain or discomfort in the upper abdomen. In addition, other symptoms that may also develop include: heartburn, bloating, belching, quickly feeling 'full' after eating, feeling sick (nausea) or vomiting. Symptoms tend to occur in 'bouts' which come and go, rather than being present all the time.

Most people have a bout of dyspepsia from time to time. For example, after a large spicy meal. In most cases it soon goes away and is of little concern. However, some people have frequent bouts of dyspepsia which affects quality of life.

What is functional dyspepsia?

Functional dyspepsia is sometimes called 'non-ulcer' dyspepsia. It means that no known cause can be found for the symptoms. That is, other causes for dyspepsia such as duodenal ulcer, stomach ulcer, acid reflux, inflamed oesophagus (oesophagitis), gastritis, etc, are not the cause. The inside of your gut looks normal (if you have an endoscopy - see below). It is the most common cause of dyspepsia. About 6 in 10 people who have recurring bouts of dyspepsia have functional dyspepsia.

What causes functional dyspepsia?

The symptoms seem to come from the upper gut, but the cause is not known. If you have tests, nothing abnormal is found inside your gut. The lining inside your gut looks normal and is not inflamed. The amount of acid in the stomach is normal.

The following are some theories as to possible causes.

• Sensation in the stomach or duodenum may be altered in some way - an 'irritable stomach'. About 1 in 3 people with functional dyspepsia also have 'irritable bowel syndrome' and have additional symptoms of lower abdominal pains, erratic bowel movements, etc. The cause of irritable bowel syndrome is not known.
• A delay in emptying the stomach contents into the duodenum may be a factor in some cases. The muscles in the stomach wall may not work as well as they should.
• Infection with a bacterium (germ) called H. pylori may cause some cases. This bacterium is found in the stomach in some people with functional dyspepsia. However, many people are 'carriers' of this bacterium, and it causes no symptoms in most people. The role of H. pylori is controversial in functional dyspepsia (although it is the main cause of duodenal and stomach ulcers). However, getting rid of H. pylori infection helps in some cases.
• Some people feel that certain foods and drinks may cause the symptoms or make them worse. It is difficult to prove this. Food is not thought to be a major factor in most cases.
• Anxiety, depression, or stress are thought to make symptoms worse in some cases.
• A side-effect of some medicines can cause dyspepsia. The most common culprits are anti-inflammatory medicines. Various other medicines which sometimes cause dyspepsia, or make dyspepsia worse, include: digoxin, some antibiotics, steroids, iron, calcium antagonists, nitrates, theophyllines, bisphosphonates. (Note: this is not an exhaustive list. Check with the leaflet that comes with your medication for a list of possible side-effects.)

What tests may be done?

Strictly speaking, functional dyspepsia is a diagnosis that is made only when no other cause can be found for the symptoms (such as an ulcer). Therefore, prior to the diagnosis being made you may have had an endoscopy. In this test a doctor looks inside your stomach and duodenum by passing a thin, flexible telescope down your oesophagus. If you have functional dyspepsia, the inside of your gut looks normal. However, most people with dyspepsia do not have an endoscopy. See separate leaflet called 'Dyspepsia (Indigestion)' for an overview of dyspepsia, and when tests are advised.

A test to detect the H. pylori bacterium may be done. If H. pylori is found then it may be causing the symptoms. A separate leaflet gives more details about H. pylori and how it can be diagnosed. Briefly, it can be detected in a small sample of faeces, or in a 'breath test', or from a biopsy sample taken during an endoscopy.

What are the treatment options for functional dyspepsia?

Reassurance and explanation
This is often helpful. Some people worry that they may have a serious disease such as stomach cancer. Worry and anxiety can make symptoms worse. It may be useful to know that you have functional dyspepsia, and not some other disease. However, you will have to accept that pain, discomfort and other 'dyspeptic' symptoms are likely to 'come and go'.

Clearing H. pylori infection
If you are infected with H. pylori, the first treatment usually tried is to clear the H. pylori infection. However, as mentioned, infection with H. pylori is probably a coincidence rather than a cause in most cases of functional dyspepsia. For example, one study found that only about 1 in 15 people with functional dyspepsia who were infected with H. pylori were cured by clearing H. pylori. (Another leaflet deals with the treatment of H. pylori. Briefly, it involves a short course of two antibiotics plus an acid suppressing medicine.)

Acid suppressing medicines
If infection with H. pylori has been ruled out, or has been treated but symptoms persist, then a medicine which reduces the acid in your stomach is often tried. A one month trial of medication is usually advised at first. This helps in some cases, but not all. It may work because the lining of your stomach may be extra sensitive to the acid. Or, it may work because you may have very mild inflammation in your stomach that 'comes and goes', but is never found if you have an endoscopy test to look into your stomach.

There are two groups of medicines which reduce stomach acid - 'proton pump inhibitors (PPIs)' and 'H2 antagonists'. They work in different ways but both reduce (suppress) the amount of acid that the stomach makes. PPIs include omeprazole, lansoprazole, pantoprazole, rabeprazole, and esomeprazole. H2 antagonists include cimetidine, famotidine, nizatidine, and ranitidine. There are several brands in each group. PPIs tend to be tried first but some people find H2 antagonists better.

If medication helps, then further courses may be advised if symptoms persist. Some people take acid suppressing medication 'on-demand' (that is, waiting for symptoms to develop before taking treatment). Some people take them regularly if symptoms occur each day.

Prokinetic medicines
Medicines called domperidone or metoclopramide are sometimes used. They help to speed up the passage of food through the stomach and may help with symptoms of bloating and feeling sick. There has been little research done to prove how effective these medicines are for functional dyspepsia, but one may be worth a try if other treatments do not help. However, they should not be used long-term as there is a risk of serious side-effects with long-term use.

Lifestyle changes
There is no clear evidence that lifestyle factors such as smoking, alcohol, caffeine, and diet affect functional dyspepsia. However, some people say that some things seem to make a difference. For example, some people say that cutting out caffeine (found in tea, coffee, cola, etc), or spicy foods, or fatty foods seems to help. If you suspect that something is making symptoms worse, it is sensible to cut it out for a while to see if it makes any difference.

If you suspect a prescribed medicine is causing the symptoms, or making them worse, then see your doctor to discuss possible alternatives.

What is the outlook (prognosis)?

Symptoms of functional dyspepsia tend to come and go. You are likely to have times when symptoms go completely, and times where they are troublesome. Functional dyspepsia does not lead to cancer or other serious illnesses.

© EMIS and PIP 2005   Updated: June 2005   PRODIGY Validated