Milder condition of unconjugated bilirubinemia (6Ð20 mg/dl); neurologic deficits occur but are less severe than in type I. Onset is usu. in infancy but as late as 2Ð10 years of age. Cause is defect in glucuronyl transferase; absence of bilirubin diglucuronide is pathognomic. Decrease in serum bilirubin after phenobarbital administration differentiates this condition from type I.