Hepatotoxins

Herbal Products

Herbal or alternative medicines, have been implicated, after the use of high dosages, in liver damage. Some of these include Ginseng, Pennyroyal oil, Teucrium polium, Chaparral or germander tea, and Kawakawa. Perceptions of safety and/or cultural mores prompt individuals to seek herbal slimming aids in preference to conventional dietary, physical activity and medication-based protocols. In recent years, terpenoid-containing dietary supplements have been implicated in causing severe and sometimes fatal hepatotoxicity. Teucrium polium (germander) was the first of these herbal products to be clearly linked to cases of acute liver failure. Subsequently, similar hepatotoxicity has been observed with other members of the Teucrium genus. While diterpenoid-derived reactive metabolites are central to germander hepatotoxicity, it may also be that the hepatic effects of compounds such as Sho-saiko-to, Centella asiatica and Black cohosh are linked to their triterpenoid content. Other non-terpenoid-containing herbal remedies marketed for weight reduction have been causally associated with significant liver injury. Important among these are preparations containing N-nitrosofenfluramine, usnic acid and ephedra alkaloids. Finally, we review recent data on known and emerging hepatotoxins such as Boh-Gol-Zhee, Kava, pyrrolizidine alkaloids and Shou-Wu-Pian. Better public and physician awareness through health education, early recognition and management of herbal toxicity and tighter regulation of complementary/alternative medicine systems are required to minimize the dangers of herbal product use.