Bilirubin will drop to normal after bile duct drainage, but it will take one to two weeks for it to begin to gradually decline to normal. Biliary drainage is used to control symptoms such as bile reflux in the bile ducts, biliary infections, and increased pressure in the bile ducts, and it can be effective in reducing the degree of jaundice in patients with biliary tract obstruction, and in reducing damage to their livers and kidneys. Bilirubin can be lowered by draining bile, thus reducing the risk of surgery. However, it should be noted that after bile duct drainage, the value of bilirubin will not immediately fall to normal, but will gradually decrease. It is important to note that after bile duct drainage, it is important to avoid eating too much greasy food and high cholesterol food, and to eat a light diet. If the bilirubin does not decrease for a long time after the operation, you need to go to the hospital immediately and take appropriate treatment under the guidance of the doctor.