Pharmacokinetic Interactions between Herbal Medicines and Drugs: Their Mechanisms and Clinical Relevance
Laura Rombolà,
Damiana Scuteri,
Straface Marilisa,
Chizuko Watanabe,
Luigi Antonio Morrone,
Giacinto Bagetta,
Maria Tiziana Corasaniti
Affiliations
Laura Rombolà
Preclinical and Translational Pharmacology, Department of Pharmacy, Health and Nutritional Sciences, Section of Preclinical and Translational Pharmacology, University of Calabria, 87036 Rende, Italy
Damiana Scuteri
Preclinical and Translational Pharmacology, Department of Pharmacy, Health and Nutritional Sciences, Section of Preclinical and Translational Pharmacology, University of Calabria, 87036 Rende, Italy
Straface Marilisa
Preclinical and Translational Pharmacology, Department of Pharmacy, Health and Nutritional Sciences, Section of Preclinical and Translational Pharmacology, University of Calabria, 87036 Rende, Italy
Chizuko Watanabe
Department of Physiology and Anatomy, Tohoku Pharmaceutical University, 981-8558 Sendai, Japan
Luigi Antonio Morrone
Preclinical and Translational Pharmacology, Department of Pharmacy, Health and Nutritional Sciences, Section of Preclinical and Translational Pharmacology, University of Calabria, 87036 Rende, Italy
Giacinto Bagetta
Preclinical and Translational Pharmacology, Department of Pharmacy, Health and Nutritional Sciences, Section of Preclinical and Translational Pharmacology, University of Calabria, 87036 Rende, Italy
Maria Tiziana Corasaniti
School of Hospital Pharmacy, University “Magna Graecia” of Catanzaro and Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy
The therapeutic efficacy of a drug or its unexpected unwanted side effects may depend on the concurrent use of a medicinal plant. In particular, constituents in the medicinal plant extracts may influence drug bioavailability, metabolism and half-life, leading to drug toxicity or failure to obtain a therapeutic response. This narrative review focuses on clinical studies improving knowledge on the ability of selected herbal medicines to influence the pharmacokinetics of co-administered drugs. Moreover, in vitro studies are useful to anticipate potential herbal medicine-drug interactions. In particular, they help to elucidate the cellular target (metabolic or transporter protein) and the mechanism (induction or inhibition) by which a single constituent of the herbal medicine acts. The authors highlight the difficulties in predicting herbal–drug interactions from in vitro data where high concentrations of extracts or their constituents are used and pharmacokinetics are missed. Moreover, the difficulty to compare results from human studies where different kinds of herbal extracts are used is discussed. The herbal medicines discussed are among the best sellers and they are reported in the “Herbal Medicines for Human Use” section of the European Medicinal Agency (EMA).
