Integrated In Silico, In Vitro, and In Vivo Approaches for Elucidating Herb–Drug Interaction Mechanisms

Herb–drug interactions (HDIs) are pharmacological events arising from concurrent use of herbal medicines and conventional pharmaceuticals, potentially leading to altered drug efficacy or toxicity. Understanding the mechanistic basis of HDIs is crucial for predicting clinical outcomes. This review synthesizes knowledge on mechanistic evaluations of HDIs using in Silico, in vitro, and in vivo models. We explore computational prediction tools, cellular and biochemical assays, and animal studies that elucidate metabolic, transport, and pharmacodynamics interactions. Strengths and limitations of each model are discussed, with recommendations for integrated approaches in preclinical and clinical research. The widespread co-administration of herbal medicines with conventional drugs has raised increasing concerns regarding herb–drug interactions (HDIs) that may compromise therapeutic efficacy and safety. Owing to the complex phytochemical composition of herbal products, mechanistic evidence supporting reported HDIs remains limited. This study aimed to systematically evaluate the molecular and pharmacokinetic mechanisms underlying herb–drug interactions using an integrated in silico, in vitro, and in vivo experimental approach. Major bioactive phytoconstituents of the selected herbal formulation were identified and subjected to in Silico molecular docking and ADME prediction to assess their interaction potential with key drug-metabolizing enzymes and transporters. In vitro enzyme inhibition and transporter assays were performed to quantify effects on cytochrome P450 isoforms and P-glycoprotein activity. Subsequently, in vivo pharmacokinetic studies were conducted in experimental animal models following co-administration of the herb and the model drug, and key pharmacokinetic parameters were analyzed to determine the magnitude of interaction. In silico analysis predicted strong binding affinities of selected phytoconstituents toward major metabolic enzymes and transporters, suggesting potential inhibitory interactions. These findings were corroborated by in vitro assays, which demonstrated concentration-dependent