Differential Diagnosis for Chronic Nausea

Chronic nausea lasting for 20 years can be caused by a variety of conditions. Here's a categorized differential diagnosis:

• Single Most Likely Diagnosis

  • Irritable Bowel Syndrome (IBS): Given the chronic nature of the nausea, IBS is a strong consideration. It's a common condition characterized by abdominal pain, bloating, and changes in bowel movements, which can also include nausea.

• Other Likely Diagnoses

  • Gastroesophageal Reflux Disease (GERD): Chronic nausea can be a symptom of GERD, especially if it's associated with eating or lying down.
  • Functional Dyspepsia: This condition involves recurring signs and symptoms of indigestion that have no obvious cause. Nausea is a common symptom.
  • Chronic Gastroparesis: A condition where the stomach takes too long to empty its contents, leading to nausea, vomiting, and feeling full after eating only a small amount of food.
  • Inflammatory Bowel Disease (IBD): Conditions like Crohn's disease and ulcerative colitis can cause chronic nausea among other symptoms.

• Do Not Miss Diagnoses

  • Gastric Cancer: Although rare, gastric cancer can present with chronic nausea and should not be missed due to its severe prognosis.
  • Pancreatic Cancer: Similar to gastric cancer, pancreatic cancer can cause chronic nausea and is critical not to miss.
  • Medullary Thyroid Carcinoma: Some cases can present with chronic nausea due to the production of calcitonin, which can affect the gastrointestinal system.

• Rare Diagnoses

  • Cyclic Vomiting Syndrome: A rare condition characterized by recurring episodes of severe nausea and vomiting.
  • Eosinophilic Gastroenteritis: A rare condition where eosinophils infiltrate the gastrointestinal tract, leading to nausea, vomiting, and abdominal pain.
  • Superior Mesenteric Artery Syndrome: A rare condition where the duodenum is compressed between the abdominal aorta and the superior mesenteric artery, leading to nausea, vomiting, and abdominal pain.

Each of these conditions has the potential to cause chronic nausea, and a thorough medical history, physical examination, and diagnostic tests are necessary to determine the underlying cause.