Bilirubin-lowering drugs: A study of the effect of methylphenobarbital, ethyl clofibrate and clofibric acid on bilirubin-albumin binding

A. Robertson, C. Cooper-Peel, Steven (Steve) Kazmierczak, R. Brodersen

Research output: Contribution to journalArticle


Objectives: To test the effect of methylphenobarbital, ethyl chlorophenoxyisobutyrate (ethyl CPIB) and chlorophenoxyisobutyric acid (CPIB) on bilirubin-albumin binding. Methods: The effect of methylphenobarbital, ethyl CPIB and CPIB on bilirubin-albumin binding by human serum albumin was determined by measuring the equilibrium concentration of free bilirubin using the peroxidase method. The effect of CPIB on bilirubin-albumin binding was further measured in human serum albumin and umbilical cord serum using the 'reverse displacement' method. The concentration of free CPIB was measured by high performance liquid chromatography after ultrafiltration by centrifugation. Results: Methylphenobarbital and ethyl CPIB do not increase the free bilirubin concentration. There is a considerable increase of free bilirubin concentration when CPIB is added to the pure bilirubin/serum albumin solutions and a lesser increase in the experiments with umbilical cord serum. Conclusions: The results confirm differences in bilirubin-albumin binding between umbilical cord serum, human serum albumin and adult serum. There is no effect of methylphenobarbital on bilirubin-albumin binding. Bilirubin displaces CPIB from binding to albumin and must be considered potentially harmful, especially if used in sick premature infants.

Original languageEnglish (US)
Pages (from-to)258-262
Number of pages5
JournalPrenatal and Neonatal Medicine
Issue number3
StatePublished - 1997
Externally publishedYes



  • Albumin
  • Bilirubin binding
  • CPIB
  • Ethyl CPIB
  • Methylphenobarbital
  • Serum

ASJC Scopus subject areas

  • Pediatrics, Perinatology, and Child Health

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