Objective Herbs have a central role in Chinese medicine. Herbs are frequently used by pregnant women and also given to newborns. Also in Western countries an increased use of herbal extracts for various conditions has been noted. In a survey in Norway (Oslo) 36% of women who had just given birth had used on average 1.7 herb products during their pregnancy and 43% used herbs during breastfeeding. Some herbs have previously been shown to displace bilirubin from albumin and thus increase the risk for bilirubin toxicity.
Methods Possible displacement of bilirubin from albumin by four commonly used different herbs, LZX-A, QTJ, YHS and SQZG, were tested against sulfisoxazole as a known bilirubin displacer. Plasma samples were obtained from jaundiced newborn infants, pooled to a bilirubin concentration of 176 µmol/l and frozen in batches at −80°C. Sulfisoxazole and herbal extracts were dissolved in 96% ethanol. Total and unbound bilirubin (UB) in plasma samples were measured with the peroxidase method (UB-Analyzer UA-1, Arrows Co. Ltd., Osaka, Japan) after addition of herbs and sulfisoxazole.
Results Sulfisoxazole (350 µg/ml) increased unbound bilirubin by 87.3%. However, no effect of the herbs on bilirubin–albumin binding could be seen at concentrations similar to therapeutic levels, not even at 10 times and 100 times therapeutic levels.
Conclusions The tested herbs do not displace bilirubin from albumin at a bilirubin concentration often seen in newborn infants. Further studies should be performed with herbs specifically given to newborns and at different bilirubin concentrations.