HERB–DRUG INTERACTIONS IN INTEGRATIVE PRACTICE: SAFETY AND EVIDENCE

As integrative medicine becomes more widely accepted, patients are increasingly taking herbal medicines from traditional systems (Ayurveda, Unani, Homeopathy) together with conventional pharmaceutical drugs. Although this combination may improve therapeutic outcomes and help with unmet needs in chronic and lifestyle-related diseases, it does create safety concerns regarding potential herb-drug interactions. Interactions can alter the way drugs work in the body (the way they are absorbed and metabolised, how they move through the body and how they are eliminated from the body) via pharmacokinetic mechanisms, and the way in which they affect our bodies via pharmacodynamic mechanisms (i.e., by adding to each other, enhancing each other, or interfering with each other). These safety concerns are even greater for patients who receive long-term therapies, take multiple medications, take drugs with narrow therapeutic indices. This chapter discusses the interactions between herbs and drugs. It starts with traditional views, and then compares those views with more modern views, using a critical approach. While discussing herb-drug interactions, a few classical concepts like Agni, Prakriti, Virdudha Dravya, Mizaj, and the principle of minimum dose will be explained. Traditional systems historically had methods of addressing the issues related to compatibility, individuality, and safety, which are also presented in the context of currently accepted medical paradigms. Examples of clinically relevant herb-drug interactions, including antidepressants, anticoagulants, antidiabetics, and anticancer medications, as well as their use and effectiveness in conjunction with Rasayana therapies, herbo-mineral preparations, and other Panchakarma therapies, will be discussed. Therefore, a major purpose of this discussion will be to highlight the potential for herb-drug interactions to cause severe or life-threatening injury in specific clinical populations, including oncology, cardiovascular/metabolic disease, neurological diseases, and psychiatric disorders. Inclusive of the discussion of this critical subject will be an emphasis on the methods for conducting safety assessments, providing risk stratification, monitoring for interactions, and performing pharmacovigilance while being aware of one's ethical responsibilities in an integrative practice and the need to be compliant with all regulatory requirements for integrative practice. Finally, emerging fields of research (systems biology, network pharmacology, and artificial intelligence) are filtering into the literature and seem to offer great promise for improving our ability to predict and manage potential herb-drug interactions. Overall, this chapter emphasizes the need for evidence-based integrative prescribing designed to promote the safe and effective use of herbs, as well as to foster the benefits that are provided by traditional and modern medicine together.