Chun-Su Yuan, MD, PhD; Gang Wei, MD, PhD; Lucy Dey, MD; Theodore Karrison, PhD; Linda Nahlik, RPh; Spring Maleckar, BA; Kristen Kasza, MS; Michael Ang-Lee, MD; Jonathan Moss, MD, PhD
Acknowledgments: The authors thank Dorothy Sellers, Jacqueline Imperial, and Linda Trumbore for their technical assistance.
Grant Support: By the National Institutes of Health (NIH) (grants AT00563, CA79042, and CA14599); NIH Clinical Therapeutics Training grant (T32-GM07019); NIH General Clinical Research Center Program grant (M01 RR00055); and Tang Center for Herbal Medicine Research at the University of Chicago.
Potential Financial Conflicts of Interests: None disclosed.
Requests for Single Reprints: Chun-Su Yuan, MD, PhD, Tang Center for Herbal Medicine Research and Department of Anesthesia and Critical Care, Pritzker School of Medicine, University of Chicago, 5841 South Maryland Avenue, MC 4028, Chicago, IL 60637; e-mail, cyuan@uchicago.edu.
Current Author Addresses: Dr. Yuan: Tang Center for Herbal Medicine Research and Department of Anesthesia and Critical Care, Pritzker School of Medicine, University of Chicago, 5841 South Maryland Avenue, MC 4028, Chicago, IL 60637.
Dr. Wei: Akros Pharma, Inc., 302 Carnegie Center, Suite 300, Princeton, NJ 08540.
Drs. Dey, Ang-Lee, and Moss: Department of Anesthesia and Critical Care, Pritzker School of Medicine, University of Chicago, 5841 South Maryland Avenue, MC 4028, Chicago, IL 60637.
Dr. Karrison and Ms. Kasza: Department of Health Studies, University of Chicago, 5841 South Maryland Avenue, MC 2007, Chicago, IL 60637.
Ms. Nahlik: Anticoagulation Consult Service, University of Chicago Hospitals, 5841 South Maryland Avenue, Chicago, IL 60637.
Ms. Maleckar: Department of Surgery, University of Chicago, 5841 South Maryland Avenue, MC 7114, Chicago, IL 60637.
Author Contributions: Conception and design: C.-S. Yuan, G. Wei, L. Dey, T. Karrison, L. Nahlik, M. Ang-Lee, J. Moss.
Analysis and interpretation of the data: C.-S. Yuan, G. Wei, L. Dey, T. Karrison, L. Nahlik, K. Kasza, J. Moss.
Drafting of the article: C.-S. Yuan, G. Wei, L. Dey, T. Karrison, K. Kasza.
Critical revision of the article for important intellectual content: C.-S. Yuan, G. Wei, T. Karrison, K. Kasza.
Final approval of the article: C.-S. Yuan, T. Karrison, K. Kasza, J. Moss.
Provision of study materials or patients: C.-S. Yuan, G. Wei, S. Maleckar.
Statistical expertise: T. Karrison, K. Kasza.
Obtaining of funding: C.-S. Yuan.
Administrative, technical, or logistic support: C.-S. Yuan, S. Maleckar.
Collection and assembly of data: C.-S. Yuan, G. Wei, L. Dey, S. Maleckar.
People using prescription medication often concurrently take herbal supplements. In a case report, the anticoagulant effect of warfarin decreased after patients consumed ginseng.
To evaluate the interactions between American ginseng and warfarin.
Randomized, double-blind, placebo-controlled trial.
General Clinical Research Center, University of Chicago, Chicago, Illinois.
20 healthy patients.
In this 4-week study, 20 patients received warfarin for 3 days during weeks 1 and 4. Beginning in week 2, patients were assigned to receive either American ginseng or placebo.
International normalized ratio (INR) and plasma warfarin level.
The peak INR statistically significantly decreased after 2 weeks of ginseng administration compared with placebo (difference between ginseng and placebo, −0.19 [95% CI, −0.36 to −0.07]; P = 0.0012). The INR area under the curve (AUC), peak plasma warfarin level, and warfarin AUC were also statistically significantly reduced in the ginseng group as compared with the placebo group. Peak INR and peak plasma warfarin level were positively correlated.
The study sample consisted of young, healthy volunteers in a research setting rather than patients taking therapeutic doses of warfarin.
American ginseng reduces warfarin's anticoagulant effect. When prescribing warfarin, physicians should ask patients about ginseng use.
Chun-Su Yuan, Gang Wei, Lucy Dey, Theodore Karrison, Linda Nahlik, Spring Maleckar, et al. Brief Communication: American Ginseng Reduces Warfarin's Effect in Healthy Patients: A Randomized, Controlled Trial. Ann Intern Med. 2004;141:23–27. doi: 10.7326/0003-4819-141-1-200407060-00011
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© 2017
Published: Ann Intern Med. 2004;141(1):23-27.
DOI: 10.7326/0003-4819-141-1-200407060-00011
Cardiac Diagnosis and Imaging, Cardiology, Coronary Risk Factors, Endocrine and Metabolism, Ethics.
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