Of all adults 30–40% experience symptoms of upper abdominal pain or discomfort but an organic cause is found in only a minority who seek medical care. The remaining group is labeled as having functional dyspepsia. Individuals with functional dyspepsia suffer significant morbidity and expend significant resources through both direct and indirect costs. Despite periods of remission, patients will usually have continued intermittent symptoms long-term with approximately 50% consulting a health care provider for their symptoms at some time in their life.
Dyspepsia is defined as having one or more symptoms of epigastric pain, burning, postprandial fullness, or early satiation. Bloating and nausea often coexist with dyspepsia but are nonspecific and are thus not included in its definition. Heartburn is also excluded from diagnostic symptom criteria for dyspepsia since it is thought to primarily arise from the esophagus and it is suggestive of gastroesophageal reflux disease (GERD) although it too may occur concomitantly. Similarly, retrosternal pain suggestive of esophageal origin such as that embraced by the term noncardiac chest pain is likewise distinguished from dyspepsia.