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Herb-drug pharmacokinetic interactions reviewed
Clemence Tarirai1, Alvaro M Viljoen, Josias H Hamman
1Tshwane University of Technology, Department of Pharmaceutical Sciences, Pretoria, South Africa.
Expert Opinion on Drug Metabolism & Toxicology
|November 12, 2010
Summary
The increasing use of herbal medicines raises concerns about herb-drug interactions, particularly pharmacokinetic ones affecting drug absorption and metabolism. More clinical data is needed to ensure patient safety with these common interactions.
Area of Science:
- Pharmacology
- Pharmacokinetics
- Herbal Medicine Interactions
Background:
- The global rise in alternative medicine use necessitates understanding herb-drug interactions.
- These interactions are critical for drugs with narrow therapeutic indices.
- Interactions can be pharmacodynamic or pharmacokinetic.
Purpose of the Study:
- To review pharmacokinetic interactions between herbs and drugs.
- To elucidate the mechanisms underlying these interactions.
- To provide examples from scientific literature.
Main Methods:
- Discussion of pharmacokinetic interactions based on primary and secondary data.
- Analysis of mechanisms affecting oral drug absorption (transporters, motility, pH).
- Examination of mechanisms impacting drug biotransformation (enzyme inhibition/induction).
Main Results:
- Comprehensive overview of herb-drug pharmacokinetic interaction mechanisms.
- An extensive list of herb-drug pharmacokinetic interactions for reference.
- Critical evaluation of reported herb-drug pharmacokinetic interactions in literature.
Conclusions:
- Herb-drug pharmacokinetic interactions are increasing globally.
- There is a growing need for clinical data on these interactions.
- Informed decisions regarding patient safety require more research.
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