galenic traditionalists later adapted medical method and some remedies to use in their own fields. history in south asia iatrochemical principles form a major part of the indian alchemical tradition (sanskrit rasaśāstra, रसशास्त्र). alchemical texts start to be composed in sanskrit in south asia from the end of the first millennium ce, and a flourishing literature developed and continued even into the twentieth century. these works contain extensive chapters on the use of alchemical recipes for healing. the use of plants, minerals and metals in medical therapeutics also existed in india. in ayurvedic medicine, substances used in these therapeutics were known as 'rasa dravyas.' ayurvedic medicine instills the belief that every material had the potential to be used as a substance. this drove the creation of new products and new uses for common substances in nature. the people of ayurvedic medicine categorize the materials in nature into three categories: 'janagama,' substances from animals such as milk, urine, blood, and meat, 'audbhida' or substances from plants such as stems, roots or leaves, and 'paarthiwa' or metal/mineral substances such as gold, silver, copper or sulfur. there was especially an emphasis on the element, mercury, in this culture. the name of these specific practices in ayurvedic medicine, were termed 'rasashaastra', which means the "science of mercury." which has eventually become known as iatrochemistry in current terminology. much of the focus of 'rasashaastra' was on the processing of these metals to become ingestible by the human body. the therapeutic effect of the materials such as metals and minerals that were known to be indigestible by the human body were combined with plants or animal materials to increase their delivery ability to human body. also see antivenom