Upper abdominal distension and abdominal pressure are commonly caused by the following reasons: perforation of the upper gastrointestinal tract, acute pancreatitis, liver and gallbladder diseases, and so on. 1. Perforation of the upper gastrointestinal tract: it is a disease of the upper abdomen, so the upper abdomen will be distended and uncomfortable, and the perforation will inhibit the function of the gastrointestinal tract, so it will lead to an increase in abdominal pressure. 2. Acute pancreatitis: the pancreas is located in the upper abdomen, after the occurrence of acute pancreatitis, the upper abdomen will be distended, the inflammation will have an inhibitory effect on the gastrointestinal function, so the abdominal pressure will increase. 3. Hepatobiliary diseases: the liver and gallbladder are located in the right upper abdomen, if acute hepatitis, acute cholecystitis and other diseases occur, the upper abdomen will be distended, inflammation will inhibit gastrointestinal peristalsis, gastrointestinal contents of the excretion of obstruction, which leads to an increase in abdominal pressure. It is recommended that the patient go to the hospital, you can improve the ultrasound, abdominal plain film and other examinations, combined with physical examination and clinical symptoms, usually can clarify the cause.