What is functional dyspepsia (indigestion)?
Functional dyspepsia, also known as non-ulcer dyspepsia or indigestion, is a term used to describe a group of symptoms affecting the gastrointestinal tract, including stomach pain or discomfort, nausea, bloating and belching. The condition is diagnosed when no obvious cause can be found for the symptoms present, though a small percentage of cases are caused by infection with the germ Helicobacter pylori. 
It is the most common form of dyspepsia and results in no serious consequences. The symptoms of the condition can often be long lasting but are manageable through a combination of lifestyle changes and medication.
Symptoms of functional dyspepsia (indigestion)
Indigestion is characterized by a group of symptoms affecting the gastrointestinal tract, including:
- Pain or discomfort in the chest or upper abdomen, usually after eating, eating too quickly or eating a heavy meal
- Bloating of the stomach
- Excessive belching
- Feeling full quickly and easily
- A feeling of extreme fullness after eating
Symptoms of indigestion will typically vary in severity from person to person and can often be vague and unpredictable. Individuals may not experience all of the dyspeptic symptoms, though most will experience more than one.
Causes of functional dyspepsia (indigestion)
Functional dyspepsia is indigestion with no clear cause (such as an ulcer, gastritis or acid reflux). The gastrointestinal tract of individuals who have been diagnosed with the disorder will appear healthy.
Despite this, there are certain triggers which may bring on or worsen the symptoms of the condition. They include:
- Smoking and alcohol
- Stress and anxiety
- Infection with the germ Helicobacter pylori (not all people with the condition will have Helicobacter pylori in their stomach, and many people with the Helicobacter pylori germ will experience no symptoms)
- Impairment of the stomach muscles, leading to slowed emptying of the stomach into the duodenum (first segment of the small intestine)
- Roughly one in three people with the disorder also experience irritable bowel syndrome (IBS). The cause of IBS, however, is unknown, meaning that the possible link between IBS and indigestion has not yet been properly established
Diagnosing functional dyspepsia (indigestion)
Diagnosing functional dyspepsia involves ruling out other conditions that may be causing the dyspeptic symptoms. Tests to check for conditions such as stomach ulcers, stomach cancer and gallstones must first return negative before a diagnosis can be given. This will usually involve undergoing a gastroscopy (endoscopy), a procedure in which a doctor will pass a small telescopic camera through the mouth and into the gastrointestinal tract for examination.
If the digestive system appears normal (free of ulcers, for example), a diagnosis of functional dyspepsia can be given. Blood tests, as well as tests to check for the presence of Helicobacter pylori, may also be useful in diagnosing the disorder.
Functional dyspepsia (indigestion) treatment
Functional dyspepsia cannot be fully cured, but its symptoms can be successfully managed through lifestyle changes, medication, or a combination of the two.
Lifestyle changes may include:
- Reducing, managing or removing any causes of ongoing stress and anxiety
- Avoiding food and drinks which make the symptoms worse (caffeinated drinks or fatty food, for example)
- Eating small, frequent meals as opposed to fewer, larger meals
- Losing weight if overweight
- Cutting down or giving up alcohol and tobacco
If lifestyle changes do not help to improve the symptoms, there are also a variety of medicines that can be effective in treating the symptoms of the condition:
- Medication to reduce acid in the stomach: Common medications which work in this way include antacids, proton pump inhibitors (such as omeprazole, lansoprazole and rabeprazole) and histamine blockers (such as ranitidine).
- Helicobacter pylori treatment: If a Helicobacter pylori infection is present, treating this with antibiotics may help to improve the symptoms.
- Pain medication: Some medications which are usually used to treat depression or pain can be used at low doses to treat functional dyspepsia. These can be helpful even for people who are not depressed.
Functional dyspepsia (indigestion) FAQs
Q: Can children be affected by functional dyspepsia?
A: Yes, pediatric functional dyspepsia is fairly common. In children, the symptoms are the same as in adults, and can be treated in a similar way. However, some medications may be unsuitable for use on children, making it important to discuss treatment methods for children with a doctor or pharmacist. Around half of all children with functional dyspepsia will begin to feel better within a few weeks. Some children, however, may have symptoms which last for a number of months.
Q: Can functional dyspepsia be cured?
A: There is no cure for functional dyspepsia. Most people manage their symptoms well with lifestyle changes and medications. Treating Helicobacter pylori (if present in the stomach) may significantly reduce the symptoms. The symptoms of the condition can be variable, and may eventually occur much less frequently or go away completely.
Q: Are there any further health implications to having functional dyspepsia?
A: Functional dyspepsia is not linked to serious illnesses such as stomach cancer.
Q: What is the prognosis for functional dyspepsia?
A: Functional dyspepsia is a persistent condition that is not associated with any serious complications, such as stomach ulcers or stomach cancer. Most people find their symptoms will come and go over time, depending on factors such as stress, lifestyle changes or other triggers. Most will also be able to manage their symptoms effectively, and some people may find that the symptoms eventually go away completely.
Q: When should I see a doctor?
A: Individuals experiencing one or more of the symptoms of functional dyspepsia should see a doctor at their earliest convenience. Based on a physical examination, a doctor will be able to make a diagnosis and offer treatment options.
People belonging to the following groups should pay particular attention to symptoms, which may be an indication of a more serious condition:
- People aged over 50
- People with a family history of digestive malignancy
- People who have previously had gastric surgery
People who experience any of the following symptoms should seek medical attention as a matter of urgency, as they may indicate a more serious condition:
- Involuntary weight loss
- Anemia or iron deficiency
- Recurrent vomiting
- Blood in the vomit
- Stool that is dark, tarry or contains blood
- Shortness of breath
- Severe pain in the neck, jaw or arms
If any of these occur, it is important to see a doctor as a matter of urgency.
Other names for functional dyspepsia
- Idiopathic dyspepsia
- Non-ulcer dyspepsia
UpToDate. “Patient education: Upset stomach (functional dyspepsia) in adults (Beyond the Basics).” July 6, 2015. Accessed July 17, 2017. ↩