Nausea is the unpleasant urge to vomit. Vomiting is the forceful ejection of stomach contents through the mouth. This is generally a protective mechanism to remove harmful ingested substances, but can occur from many unrelated infectious and inflammatory conditions in the body. Dehydration and/or imbalance of the body’s electrolytes and minerals circulating in the blood can be problematic when vomiting is severe or prolonged. When symptoms are prolonged, weight loss or malnutrition may occur. A consultation with your gastroenterologist may be necessary to identify the cause of chronic nausea and vomiting. If the diagnosis still remains unclear after a history and physical, the following tests may be used to provide your gastroenterologist with more information: A) Blood tests (blood count, measurement of chemical levels in the blood, liver and pancreatic enzymes); B) X-rays of the gastrointestinal tract, abdomen, or brain. These can include plain x-rays, barium x-rays or specialized scans such as CT scans or MRI scans; C) Endoscopy to look for abnormalities in the lining of these structures that might be causing the nausea and vomiting; D) Tests to assess the movement of food through the stomach and intestines, gastrointestinal motility testing.