The abdomen describes the region of the body that expands from the chest cavity to the pelvis. Because so many organs reside in the abdominal cavity, abdominal pain can occur due to many different conditions. The intensity of the abdominal pain does not always indicate the seriousness of the underlying condition, as indicated by MedLine Plus, a website of the National Institutes of Health. Conditions that cause upper abdominal pain along with nausea range from the simple stomach flu to more serious conditions such as acute pancreatitis.
Approximately 1 billion episodes of gastroenteritis, commonly called the stomach flu, occur worldwide each year, according to the Merck Manual. Gastroenteritis describes a group of illnesses that cause inflammation of the lining of the stomach, small intestine or large intestine.
Viruses such as the rotavirus or norovirus cause viral gastroenteritis with symptoms including upper abdominal pain, nausea, vomiting and watery diarrhea. The viruses usually spread through hand to mouth contact but can also be spread through contaminated foods when food handlers with the virus fail to wash their hands.
Bacteria such as E. coli and salmonella cause bacterial gastroenteritis, often referred to as food poisoning. Giardia, a parasite commonly found in water sources, also causes gastroenteritis. Symptoms include abdominal cramps or pain often in the upper region, nausea, vomiting, bloody stools and loss of appetite. Infection with these organisms usually occurs through contaminated food or drink products.
The pancreas, a large gland located behind the stomach, secretes digestive enzymes into the small intestines and produces the hormones insulin and glucagon necessary for glucose regulation. Acute pancreatitis, the sudden onset of inflammation of the pancreas, usually occurs due to the presence of gallstones but may also occur due to abdominal trauma, medications or infections. Acute pancreatitis, a possibly life-threatening illness, affects approximate 210,000 people in the United States each year, as reported by the National Digestive Diseases Information Clearinghouse.
Symptoms include gradual or sudden upper abdominal pain that can extend to the back, nausea, vomiting, fever and rapid pulse. A severe episode can result in dehydration and low blood pressure leading the heart, lungs or kidneys to fail.
The gallbladder, a small pear-shaped organ found in the right side of the abdominal cavity, functions to store bile, a digestive fluid produced in the liver. It contains cholesterol, fats, water, proteins, salts and the waste from red blood cells known as bilirubin. Inflammation of the gallbladder, a condition known as cholecystitis, causes severe upper abdominal pain, nausea, vomiting, sweats, loss of appetite, fever and chills.
Cholecystitis often occurs due to the presence of gallstones, tiny hard stones formed when substances in the bile such as cholesterol crystallize. In addition to causing inflammation of the gallbladder, gallstones can leave the gallbladder and enter the bile ducts causing a blockage in the duct. This causes a sudden onset of symptoms, often referred to as a gallbladder attack, which is characterized by severe upper abdominal pain, nausea, vomiting and fever.