Unani concept of drug substitution (therapeutic interchange) and its validation on scientific parameters

Background: Unani concept of therapeutic interchange, despite having immense practical aspect, has notbeen touched upon in a coherent way by most of the Unani scholars except Razi (Rhazes 865e925 AD),who took the concept plausibly and framed rules for alternate drug prescription at the time ofunavailability of the drugs of choice.Objective: The Unani concept of therapeutic interchange is based on similarity in action, temperamentand physical properties of drugs mainly botanicals, which are already established and need no furtherdiscussion; however, phytochemistry has not been considered a basis for substitution. Therefore,objective of this study was evaluation of the concept on phytochemical parameters as actions of mostdrugs are due to phytoconstituents.Material and methods: Classical Unani literature pertaining to therapeutic interchange and ethnobotanical literature for uses and phytoconstituents of three botanicals and their respective substitutes werereviewed. Ethnobotanical literature was collected from well known search engine viz., PubMed, GoogleScholar, Scopus and Science direct. In view of exploring the concept on scientific basis, physicochemical,phytochemical and analytical (HPLC, GCeMS) studies were also conducted.Results: The study exhibited similarity in phytoconstituents in main and substitute botanicals withinsignificant differences. Direct relation between doses, actions, intensity of actions, temperament andchemical constituents of main and substitute botanicals was observed.Conclusion: The study, however, seemed to validate the concept on the basis of phytoconstituents, furtherpharmacological studies on the basis of properties and activities is required to strengthen the concept