Functional Dyspepsia (Non-Ulcer Dyspepsia, Indigestion)

Dyspepsia means indigestion or discomfort in the stomach area, often associated with eating or drinking. Functional dyspepsia (FD) is a functional gastrointestinal disorder, which means that routine testing of the gastrointestinal tract usually shows normal results.

Functional gastrointestinal disorders stem from an altered gut–brain interaction, meaning that there is miscommunication between the gut’s nervous system and the brain’s nervous system. This results in symptoms such as stomachache, fullness, and nausea.

People with FD may experience heartburn, fullness after a meal or before finishing a meal, nausea after meals, excessive belching, and pain, burning, or bloating in the upper abdomen.

FD can be caused by many factors, including changes in the gastrointestinal tract, genetics, environmental influences, and psychological temperament. Examples include:

• Abnormal motility: After a meal, the stomach normally expands to allow more space for the food. After food is digested, it then normally passes out of the stomach and into the intestines. In patients with FD, the stomach may not expand properly, or passage of digested food out of the stomach is slowed. This causes a feeling of fullness.
• Visceral hypersensitivity: Patients with FD may have visceral hypersensitivity, which means that nerves in the gastrointestinal tract are overactive and highly sensitive. This causes increased pain even during normal stomach function (for example, food stretching the stomach as it passes through).
• Infection and inflammation: FD can develop in children after they have a bacterial infection of the gastrointestinal tract. Some patients have undetectable inflammation in the stomach or small intestine, which may affect function of these organs.
• Microbiome: The gastrointestinal tract contains bacteria and other microorganisms that help keep it healthy. This is called the “microbiome”, and it is unique to every individual and is influenced by genetics and diet. People who have FD may have different gut bacteria than people without FD. This difference in gut bacteria may make FD worse.
• Food sensitivity: Food and diet likely impact FD. Some people experience more symptoms after consuming specific foods, called trigger foods.
• Stress: FD is caused by miscommunication between the brain and gastrointestinal tract. Changes in mood, increased anxiety, and physical stress likely alter this communication. While stress and anxiety do not solely cause symptoms of FD, they can worsen the symptoms. How the brain and gut interact likely affects the severity of symptoms and the patient’s illness.

FD is less common than other gastrointestinal conditions, affecting about 5%–10% of children and adolescents.

Symptoms may be associated with mealtime and include:

• Fullness after a meal
• Fullness before finishing a meal
• Nausea after meals
• Pain, burning, or bloating in the upper abdomen
• Excessive belching

There is no specific test to diagnose FD. Rather, a thorough evaluation and physical exam by your child’s healthcare provider is needed for diagnosis. Certain signs and symptoms called the “Rome Criteria” help providers make an appropriate diagnosis. Relevant signs and symptoms include:

• One or more of the following bothersome symptoms at least 4 days per month, for at least 2 months:
  • Fullness after a meal
  • Fullness before finishing a meal
  • Upper abdominal pain, not related to bowel movements

Testing is often not needed to diagnose FD, although your child’s healthcare provider may order some simple screening tests to look for any additional causes of pain. Testing is specific to each patient but may include:

• Blood tests
• Stool studies
• Abdominal ultrasound to look at organs in the abdomen
• Gastric emptying study to see how well the stomach empties
• Upper endoscopy to check for inflammation or infection. This is done using a camera that is passed through the mouth to look at the esophagus, stomach, and small intestine.

Treatment for FD depends on your child’s main bothersome symptoms. Treatment can include medications, dietary changes, and lifestyle modifications. Usually, more than one treatment is used.

Dietary changes include:

• Smaller, more frequent meals
• Avoiding fatty or spicy foods
• Avoiding carbonated drinks
• Avoiding caffeine
• Avoiding medications called non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, (brands such as Motrin and Advil), naproxen (brands such as Aleve), Excedrin, Alka-Seltzer, diclofenac, and meloxicam (brands such as Mobic).

If your child’s main symptom is fullness:

• A medicine called cyproheptadine (pronounced sip-ro-hep-ta-deen) can be used to help the stomach expand to allow more space for food and to help food pass out of the stomach.
• Products containing peppermint oil have been helpful in some patients.
• Prokinetics, or medications that relax the stomach, can help alleviate symptoms.
• Treatment with anti-emetic medications can help prevent nausea.

If your child’s main symptom is pain or burning:

• Acid-blocking medicines can help alleviate symptoms.
• Antidepressant medications can improve abdominal pain symptoms by targeting nerve hypersensitivity in the gastrointestinal tract. Tricyclic antidepressants (TCAs) and selective serotonin reuptake inhibitors (SSRIs) are specific classes of antidepressants/antianxiety medications that can help treat FD symptoms in children.

There also is some evidence that probiotics are safe and may help relieve symptoms of FD.

Treatments to promote relaxation, like counseling, yoga, acupuncture, hypnosis, and guided imagery, also may help.

If medicines, dietary changes, and lifestyle changes do not help your child, some medical centers can offer a treatment called gastric electrical stimulation, which stimulates the stomach with electrodes.

Every child is different, and your doctor may use one or more ways to treat FD. It is important to talk to your child’s healthcare provider/gastroenterologist about the best treatment plan for their FD symptoms. A combination of lifestyle changes and medication may be recommended to see the most improvement in symptoms.

Discuss with your child’s healthcare provider what signs and symptoms require urgent medical attention. In general, you should contact your child’s healthcare provider/gastroenterologist or go to the nearest emergency department if your child experiences any of the following:

• Persistent or severe vomiting
• Black stool or blood in stool
• Severe pain that is different from your child’s usual pain
• Right-sided upper abdominal pain
• Fever higher than 101ºF
• Pain that wakes your child from sleep

While every child is different, symptoms eventually go away in about half the patients. About 20% of patients have persistent symptoms, and about 30% have symptoms that come and go. Although symptoms can sometimes interfere with your child’s functioning, there is no evidence to suggest that FD will cause long-term harm to your child.

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Written by: Jonathan Gisser, MD
Edited by: Athos Bousvaros, MD
May 2021