Effect of Sodium Phenobarbital on Bilirubin Metabolism in an Infant with

mones, compounds capable of hepatic enzyme induction, were given to an infant boy with congenital, nonhemo-lytic, unconjugated, hyperbilirubinemia and severe kernicterus for prolonged periods between the ages of 2 and 25 months to determine their effect on serum bili-rubin concentrations. Phenobarbital, 5 mg/day orally, on two occasions decreased serum bilirubin concentra-tions approximately threefold over a period of 30 days. Withdrawal of phenobarbital after the first study re-sulted in a gradual (30 days) return of serum bilirubin to pretreatment levels. The lower serum bilirubin con-centrations observed when phenobarbital therapy was reinstituted were maintained for 61 days on 2.5 mg/kg per day of the drug. Orally administered L-triiodothyro-nine, 0.05-0.1 mg/day for 71 days, intramuscular human growth hormone, 1 mg/day for 21 days, and testosterone propionate, 0.1 mg/day for 9 days, did not decrease se-rum bilirubin levels below lowest control values of 18 mg/100 ml. Bilirubin-'H was administered twice before and once with bilirubin-"C during phenobarbital therapy to study the kinetics of bilirubin metabolism. Results of the first and second control studies and of the bilirubin-'H and bilirubin-"C phenobarbital studies, respectively, wer