Planta Med 2012; 78(13): 1478-1489
DOI: 10.1055/s-0031-1298273
Examples of Herb-Drug Interactions
© Georg Thieme Verlag KG Stuttgart · New York

Pharmacokinetic Herb-Drug Interactions (Part 1): Origins, Mechanisms, and the Impact of Botanical Dietary Supplements

Bill J. Gurley1
  • 1Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, College of Pharmacy, Little Rock, Arkansas, United States
Further Information

Publication History

received Dec. 15, 2011 revised January 23, 2012

accepted January 25, 2012

Publication Date:
09 February 2012 (online)


Phytochemicals have been components of man's diet for millennia and are believed to have played a significant role in steering the functional development of xenobiotic metabolizing enzymes and transporters within the human gastrointestinal tract. Only recently, however, have plant secondary metabolites been recognized as modulators of human drug disposition. Despite exposure to thousands of structurally diverse dietary phytochemicals, only a few appear to significantly modulate human drug metabolizing enzymes and transporters. In some instances, these interactions may have beneficial effects like cancer prevention, whereas others may dramatically affect the pharmacokinetics of concomitantly administered drugs. In today's global economy, the opportunity for exposure to more exotic phytochemicals is significantly enhanced. Formulated as concentrated phytochemical extracts, botanical dietary supplements are vehicles for a host of plant secondary metabolites rarely encountered in the normal diet. When taken with conventional medications, botanical dietary supplements may give rise to clinically significant herb-drug interactions. These interactions stem from phytochemical-mediated induction and/or inhibition of human drug metabolizing enzymes and transporters.


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Dr. Bill J. Gurley

Department of Pharmaceutical Sciences
University of Arkansas for Medical Sciences
College of Pharmacy

4301 W. Markham St.

Little Rock, Arkansas 72205

United States

Phone: +1 50 16 86 62 79

Fax: +1 50 15 26 65 10