Dr. Gyanendra Pandey is an Ayurvedic scholar whose three-volume Dravyaguna Vijnana enumerates more than five hundred medicinal plant drugs drawn from the indigenous materia medica of Ayurveda. Written in English with supporting Sanskrit text and classical references, the set was produced between 1998 and 2001 and covers drugs in alphabetical order across three volumes. It addresses the pharmacology and therapeutics of vegetable-origin drugs within the framework of Indian medical science.