<p>Ayurveda is the system of health care indigenous to India with an impressive evolutionary history spanning a period of more than 2000 years. Ayurvedic pharmacopoeia includes thousands of herbal and herbo-mineral formulations indicated in the management of diverse diseases. Ayurveda continues to be practiced in the country of its origin and is also emerging as an alternative approach to health care in many countries around the world. There are reports of toxicity associated with the use of Ayurvedic medicines and regulatory authorities are raising their eyebrows expressing concern about the safety of Ayurvedic formulations. This paper is an attempt to review the toxicity and safety of Ayurvedic formulations from the ancient and modern perspective. A careful review of Classical Ayurvedic literature clearly reveals that there are well established protocols and practices to check for toxicity and safety of drug sources as well as formulated drugs. The texts emphasize a comprehensive study of every drug source both in term of their short term and long-term effects on the human body. Toxic substances were identified and classified separately. Ayurvedic texts elaborately discuss about protocols and guidelines for safe use of medicinal substances and developed methods of purification of drugs to render them safe for human use. Ayurveda proclaims that there is no substance that is absolutely safe, and that safety can be assured only by proper use of a substance. The pros and cons, the risks and benefits have to be assessed in a given context to ensure beneficial outcomes. An unknown substance therefore is likely to cause more harm than a substance that has been adequately studied. On the other hand, abuse of known substances can also lead to undesirable outcomes. In India, Ayurvedic medicines are consumed on a large scale by its huge population. Toxicity of Ayurvedic medicines have been reported due to presence of toxic metals like lead, mercury and arsenic. In the case of herbal medicines, this is attributable to environmental pollution or bad manufacturing practices. However, the intentional use of mercury, arsenic and such other toxic substances as medicine has spurred debate amongst scientists and the laity regarding the safety of Ayurvedic medicines. Modern researchers find it hard to accept that highly toxic metals and minerals can ever be rendered safe for human use by any method of processing. On the other hand, the Ayurvedic physicians maintain that purification of toxic substances is very much possible if done meticulously. This paper examines the available evidence in support of these viewpoints even as it identifies the gaps and suggesting pointers for further research.</p>
Ram Manohar P., “Toxicity of Ayurvedic Medicines and Safety Concerns: Ancient and Modern Perspectives”, in Toxicology in Antiquity (Second Edition), Second Edition., P. Wexler, Ed. Academic Press, 2019, pp. 441 - 458.