The pain in the right upper abdomen should be considered for diseases of the hepatobiliary system, such as acute hepatitis, chronic hepatitis, liver tumors, and fatty liver, which can lead to an increase in liver size and pull the surface of the liver envelope, which can cause painful sensations. Diseases of the gallbladder, including acute and chronic cholecystitis, adenomyosis of the gallbladder, gallbladder cancer, and embedded stones in the biliary system, can cause pain in the right upper abdomen, which may be accompanied by jaundice and fever. In addition, diseases of the tail of the pancreas, such as inflammatory and neoplastic diseases, can also cause pain in the left upper abdomen, and respiratory system, such as bilateral pleurisy and lobar pneumonia of the lower lobe, can also cause pain in the right and left upper abdomen.