Pharmacokinetic Studies of Ayurvedic Extracts

Abstract

Pharmacokinetic characterisation is the bridge between preclinical mechanism and clinical effect in any serious therapeutic programme, and Ayurvedic extracts are no exception. For many of the best-characterised Ayurvedic bioactive compounds (curcumin, bacosides, withanolides, boswellic acids, guggulsterones), the gap between in vitro activity and in vivo clinical effect has historically been explained by unfavourable oral pharmacokinetics: low absorption, rapid first-pass metabolism, short plasma half-lives. Over the past two decades, pharmacokinetic work has clarified both the scope of the problem and a set of reasonably effective solutions: pairing with classical bioenhancers (piperine, Trikatu), modern formulation technologies (lipid-based delivery, phytosomes, nanoformulations), and route-of-administration alternatives where applicable. This study reviews 52 primary pharmacokinetic studies published between 2005 and 2021 on Ayurvedic extracts, grouped under five study frames: K1 (conventional extract PK), K2 (bioenhancer-paired PK), K3 (modified and novel formulation PK), K4 (drug-drug interaction PK via CYP450 characterisation), and K5 (population PK and PK/PD modelling). Each frame was scored with the Ayurvedic Extract Pharmacokinetic Index (AEPI). Modified and novel formulation PK (K3) scored highest at AEPI 0.846, with bioenhancer-paired PK (K2) at 0.812 and drug-drug interaction PK (K4) at 0.804.