The Effect of Some Complementary Medicine Active Components on Rat Embryonic Heart Rate In Vitro

INTRODUCTION: Most complementary and alternative medicines (CAMs) lack clinical safety regarding use in pregnancy, yet they are freely available and do not require a prescription. While all new conventional medicines are assessed for safety during pregnancy, CAMs are exempt. In vitro testing potentially provides a rapid screening method to support risk assessment. Whole rat embryo culture can be used to identify the impact of chemicals on the embryonic heart rate. There is clear evidence that slowing of the embryonic heart rate (bradycardia) can cause spontaneous abortions and fetal malformations. The aim of this study was to examine the effect of four commonly used CAMs on the embryonic heart rate in vitro. A risk assessment was then generated from the results. METHODS: Gestation day 13 rat embryos were exposed to the active ingredient of four herbal medicines: allicin (garlic), epigallocatechin-gallate (green tea), ginsenoside Rg3 (found in ginseng), and berberine (goldenseal). All ingredients caused embryonic bradycardia. RESULTS AND CONCLUSION: The margin of safety was acceptable for EGCG and ginsenoside Rg3 but could not be calculated for allicin due to lack of pharmacokinetic data. The margin of safety for berberine is also likely to be acceptable under most conditions.