High jaundice in babies refers to the high concentration of bilirubin in the baby’s body, and the common types are physiological jaundice and pathological jaundice. Physiological jaundice mostly occurs in newborns, usually without obvious symptoms of discomfort, commonly manifested as mild yellowing of the skin or sclera, which usually subsides on its own after a period of time. If the symptoms continue for a longer period of time and gradually worsen, or if the symptoms are recurrent, pathological jaundice is considered. Pathological jaundice is often caused by various factors that lead to an abnormal increase in serum bilirubin levels, and may have a long duration or recurrent symptoms. Other physical symptoms may vary according to the degree of jaundice. In mild cases, the infection may appear on the face and extremities, and as the disease progresses, the yellowish tinge may increase, spreading from the face to the body and then to the extremities. The color can change from golden yellow to grayish yellow, dark yellow, or even yellowish green. As the disease worsens, the color of urine and tears may also change to yellow. In severe cases, the baby may become anorexic, depressed or even have difficulty breathing, and may even suffer from convulsions, screaming and respiratory failure, which may result in death in severe cases. Jaundice may lead to complications such as acute bilirubin encephalopathy and nuclear jaundice as the disease progresses, resulting in neurological sequelae. Common manifestations of acute bilirubin encephalopathy include drowsiness, fever, convulsions, etc. In severe cases, apnea may occur, and nuclear jaundice may develop with longer duration. Nuclear jaundice is permanent central nervous damage and can be severe enough to cause sequelae such as cerebral palsy and head lifting weakness.