Typically, you'll get results for direct and total bilirubin. Normal results for a bilirubin test are 1.2 milligrams per deciliter (mg/dL) of total bilirubin for adults, and usually 1 mg/dL for those under 18.Normal results for direct bilirubin are generally 0.3 mg/dL. These results may vary slightly from laboratory to laboratory.igher than normal levels of direct bilirubin in your blood may indicate your liver isn't clearing bilirubin properly. Elevated levels of indirect bilirubin may indicate other problems. One common, and harmless, cause of elevated bilirubin is Gilbert's syndrome, a deficiency in an enzyme that helps break down bilirubin.