Differential Diagnosis for Chronic Nausea

Single Most Likely Diagnosis

• Gastroesophageal Reflux Disease (GERD): This is often the most common cause of chronic nausea due to the reflux of stomach acid into the esophagus, leading to symptoms like heartburn and nausea.

Other Likely Diagnoses

• Functional Dyspepsia: A condition characterized by recurring signs and symptoms of indigestion that have no obvious cause, often leading to chronic nausea.
• Irritable Bowel Syndrome (IBS): While primarily known for causing abdominal pain and changes in bowel movements, some patients with IBS may experience chronic nausea.
• 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 gastrointestinal symptoms.

Do Not Miss Diagnoses

• Pregnancy: Morning sickness can sometimes persist throughout the day and last beyond the first trimester, making it a critical diagnosis not to miss.
• Medication Side Effects: Many medications can cause nausea as a side effect, and identifying the culprit can lead to a simple resolution by changing the medication.
• Malignancy: Although rare, certain cancers (like pancreatic cancer) can present with chronic nausea, making it essential to rule out in the appropriate clinical context.
• Infections: Chronic infections such as giardiasis or other parasitic infections can cause prolonged nausea.

Rare Diagnoses

• Cyclic Vomiting Syndrome: A rare condition characterized by episodes of severe nausea and vomiting that can last for hours or even days, with periods of normal health in between.
• Eosinophilic Gastroenteritis: A rare condition where eosinophils (a type of white blood cell) accumulate in the gastrointestinal tract, leading to nausea, vomiting, and abdominal pain.
• Superior Mesenteric Artery Syndrome: A rare condition where the duodenum (the first part of the small intestine) is compressed between the abdominal aorta and the superior mesenteric artery, leading to nausea, vomiting, and abdominal pain.
• Neurological Disorders: Certain neurological conditions, such as vestibular disorders or brain tumors, can cause chronic nausea, often accompanied by other neurological symptoms.