The gallbladder is one of the organs that make up the digestive system and has the function of storing bile and concentrating it. After gallbladder removal, eating especially greasy food may cause the bile excreted by the liver to enter the gastrointestinal tract directly without being stored through the gallbladder causing irritation and damage to the mucosa. Some patients can develop bile reflux gastritis, where stomach contents containing excess bile flow back into the oesophagus, manifesting as a bitter mouth.