Assessing the safety of Echinacea using a metabolomic approach

As herbal medicinal products rapidly gain popularity, their interactions with conventional drugs becomes an increasingly important safety concern. A major pathway for interactions is via the cytochrome P450 (CYP) system, which is responsible for the detoxification and metabolism of endobiotics and xenobiotics. We have used in vitro assays on purified CYP enzymes to investigate the potential of Echinacea for inhibiting CYP3A4, a major CYP isoform. A number of commercially available Echinacea liquid preparations (ELP) weakly inhibited CYP3A4, but with a wide variation in potency (IC50: 12–1817µg/ml) and alkylamide…