Comprehensive review of hepatotoxicity associated with traditional Indian Ayurvedic herbs

With growing antipathy toward conventional prescription drugs due to the fear of adverse events, the general and patient populations have been increasingly using complementary and alternative medications (CAMs) for managing acute and chronic diseases. The general misconception is that natural herbal-based preparations are devoid of toxicity, and hence short- and long-term use remain justified among people as well as the CAM practitioners who prescribe these medicines. In this regard, Ayurvedic herbal medications have become one of the most utilized in the East, specifically the Indian sub-continent, with increasing use in the West. Recent well-performed observational studies have confirmed the hepatotoxic potential of Ayurvedic drugs. Toxicity stems from direct effects or from indirect effects through herbal metabolites, unknown herb-herb and herb-drug interactions, adulteration of Ayurvedic drugs with other prescription medicines, and contamination due to poor manufacturing practices. In this exhaustive review, we present details on their hepatotoxic potential, discuss the mechanisms, clinical presentation, liver histology and patient outcomes of certain commonly used Ayurvedic herbs which will serve as a knowledge bank for physicians caring for liver disease patients, to support early identification and treatment of those who present with CAM-induced liver injury.