Symptoms of high bilirubin levels include jaundice, itchy skin, fatigue, dark urine and low appetite, explains Healthline. When a patient's bilirubin levels are high, the doctor conducts further tests to determine the cause, according to WebMD.
High bilirubin levels may indicate liver damage due to cirrhosis or hepatitis or blocked bile ducts due to gallstones, states WebMD. High bilirubin levels are also a sign of gallbladder infection, rapid destruction of red blood cells or an allergic reaction to blood received during a transfusion. Medications that may increase bilirubin levels include many antibiotics, certain birth control pills, flurazepam, diazepam and indomethacin.