Abstract

Poisoning changes over time. A patient may first have local or gastrointestinal symptoms and later develop neurological, cardiovascular, respiratory, hepatic or renal injury. Modern toxicology explains this progression through toxicokinetics, which describes absorption, distribution, metabolism and excretion, and toxicodynamics, which describes the biological effects produced at target tissues. Ayurvedic toxicology, or Agada Tantra, describes the evolving manifestations of poison through concepts such as Visha Guna, Visha Gati and Visha Vega. This narrative review compares these frameworks without treating them as identical. Classical descriptions from the major Ayurvedic texts were considered alongside current toxicology literature on disposition, overdose, target-organ injury and elimination. The comparison suggests that Visha Vega is best understood as a qualitative, stage-based clinical account of changing poisoning, whereas toxicokinetics is a quantitative account of how a toxicant moves through the body. Toxicodynamics provides an important bridge because many manifestations used to recognize a Vega reflect tissue effects rather than movement of the toxicant alone. Directly equating individual Vega with separate ADME steps is not scientifically justified. Future research should use prospective, time-linked observations that record classical symptom clusters together with toxicant concentrations, metabolites, physiological measurements and organ-specific biomarkers.