Ginseng, Coffee, Herb-Drug Interactions, and Evidence-Based Medicine
June 12th, 2009
Ginseng, Coffee, Herb-Drug Interactions, and Evidence-Based Medicine
Published on June 12th, 2009 @ 12:43:05 am , using 1632 words, 2096 views
By Eric Brand
Many of our regular readers know that I have a passion for ginseng. I only eat it sporadically but I love learning about it, and I go to great lengths to go all over China to seek out experts and specimens to fill in the remaining gaps in my knowledge and experience. You can read one of my ginseng blogs at: http://www.bluepoppy.com/blog/blogs/blog1.php/2009/04/02/ginseng-cultivated-vs-wild-a-general-dis
Follow up:
Given this passion, I am particularly offended when I see misinformation about ginseng. Like most of us, I am used to seeing scientific papers on Chinese herbs that are done without a shred of scientific integrity- studies done without verifying the authenticity of the botanical specimens, studies done without paying attention to the dosage in the literature or the clinical reality of traditional use… Most of these egregious errors come from a simple lack of education on the part of the researchers, so I don’t get too worked up about it. But I must confess that it really irks me when I find primary herbal resources that spread misinformation within our core professional community.
In most situations, these errors could be minimized with extremely basic efforts at rigor and scholarship. For example, the European ESCOP monographs are one of the most widely used and well-regarded resources in Western herbalism. They have an extensive section on ginseng, complete with an impeccable scientific review and a variety of excellent features. Yet they report the dose of ginseng as 0.5-2.0g per day, with anything over two grams considered overdose. Seriously, are they for real? How could a whole team of scientists and herbalists create a monograph on ginseng without noticing that the traditional and standard clinical dose range of ginseng is 3-9 grams per day? I mean, it isn’t rocket science to determine that ginseng is an herb with an extensive history of use in traditional East Asian medicine, and all the pharmacopoeias in the East clearly list this higher dose range. (Actually, I guess it would be more accurate to say that ginseng was traditionally used in doses of 4-11 g/day, with high doses going up to 37.5 g/day… to read about weights and measures in TCM, see our Blue Poppy blog at http://www.bluepoppy.com/blog/blogs/blog1.php/2009/02/11/how-much-is-in-a-qian)
Ok, so I should cut the Europeans some slack. Maybe the authors were culturally insulated, maybe no one on the committee could read Chinese or no one had studied TCM. In an ideal world, a monograph on a Chinese medicinal would be done with a team that included someone who had access to the primary literature or had a clue about its traditional use, but I will forgive this gross error because these people are Western herbalists rather than TCM experts.
By contrast, I am really bothered by the statement in Bensky, Clavey, and Stoger’s Chinese Herbal Medicine Materia Medica that ginseng should not be used with coffee or other stimulants. Maybe I’m biased because I import ginseng and I don’t want to have the market damaged by a generation of misinformed practitioners. Or maybe I just hold Bensky’s team to a standard that is too high, because I know that Bensky, Clavey, and Stoger are all experts within the field that should know better.
Regardless, I think that their materia medica evinces true scholarship in many ways. For example, Erich Stoger’s breakdown of the botanical differences is a monumental work of fantastic academic caliber. Even in the Chinese literature, pharmacy information of this degree of scholastic excellence is hard to find. In fact, I think that it is precisely because of the excellent level of general scholarship throughout the book that I feel that the masterpiece is smudged by things like the ginseng-coffee statements or sloppy translations of TCM actions of herbs (see http://www.bluepoppy.com/blog/blogs/blog1.php/2009/06/02/on-nigel-wiseman-and-practical-dictionar).
Ginseng and Coffee
Bensky et al’s Materia Medica text is far from the first source to propose the idea that ginseng should not be combined with coffee or other stimulants. Under the “key points” contraindications section of this book, it states that “It [ginseng] should not be taken with coffee or other stimulants.” This same statement can be found nearly verbatim in a number of other English texts on Western herbalism. However, almost none of the books that contain this statement list any citations for this claim. In the lone exception in the literature where this statement occurs and a citation is given, the referenced article itself lacks any mention of ginseng and coffee or any other stimulants. In other words, this is basically hearsay based on secondary sources, with a complete absence of traditional and modern literature that supports this claim.
It is, indeed, a bold claim to suggest that ginseng cannot be used with coffee or other stimulants. Ginseng is the most famous herb in East Asian medicine. Coffee is just about the most widely-used herbal product in the world. Millions of people consume ginseng and coffee together every day in Korea alone, much less the rest of the world. A proven herb-herb or herb-drug interaction with ginseng and coffee or other stimulants would be headline news. Yet this evidence is strikingly lacking.
By contrast, even a cursory analysis of research papers reveals that ginseng has been used with a wide variety of stimulant drugs in both human and animal studies. Ginseng has been combined with amphetamine, methamphetamine, and cocaine in numerous clinical trials and animal models, and nearly all of these trials have demonstrated positive effects in which the side effects and dangers of the stimulants were reduced with concurrent administration of ginseng. To my knowledge (and I’ve looked long and hard), there are no articles with a decent study design that demonstrate any negative consequences of using ginseng with coffee or caffeine. Clearly, if we are going to pay attention to the scientific evidence base, there is little evidence to support the claim that ginseng should not be used with coffee or other stimulants.
Naturally, I’m not one to stop looking when I’ve exhausted the biomedical databases like Pubmed. Coffee is not a traditional substance in TCM, but it does appear in TCM materia medicas and dietary therapy texts. Nonetheless, a thorough search of traditional Chinese sources was completely fruitless to find any evidence of this contraindication. Having already scoured the University of California medical databases, the Chinese traditional literature, and the whole Redwing warehouse of holistic books, I started emailing experts to see if there were sources that I was missing (remember, I am a nerd with a passion for ginseng). I emailed the chief editor of the ESCOP monograph on ginseng as well as John Chen, who is a TCM practitioner and PharmD with expertise on herb-drug interactions. Both of them replied and said that they had never seen anything in the literature to support this claim. I did receive a reply from John O’Conner at Eastland with a promise to investigate the source of the original statement in the Bensky book, but no further reply ever came to clarify the source. Thus, I can only conclude that if evidence for this contraindication exists, it is very isolated and has never been replicated.
In this case, it is most likely that the reason for this caution is due to the popular conception that ginseng is itself a stimulant. However, ginseng is not a stimulant drug in terms of modern pharmacology; it has both stimulating and inhibitory constituents, which gives it an overall regulating and balancing effect on the body. The idea that ginseng=stimulant and thus should not be combined with other stimulants is based on a flawed and simplistic understanding of the actions of ginseng. Certainly this simplistic thinking is not the standard that professional practitioners are shooting for, and it damages our profession if we espouse opinions that cannot be backed up with either science or tradition.
Why do I care so much about this? For starters, I sell ginseng, and my dad consumes ginseng and coffee with great regularity. If there is a true risk of a harmful interaction, I need to know about it. I would love to learn about any sources or research that elucidate this issue, so please send me sources for further reading if you are reading this blog and can help me out.
Beyond my own personal interest in not having my father keel over from his ginseng and coffee habit, I truly want to see our field move beyond reliance on secondary sources. We are the only field in the entire medical community that bases our medical decisions on secondary sources rather than primary sources like original Chinese literature or scientific studies. For the entire history of the US licensing exams, there has only been one materia medica on the exam list. This allows a single book to be treated like gospel, and if that one book tells thousands of students that ginseng cannot be used with coffee or other stimulants, it will influence the prescribing habits, opinions, and recommendations of thousands of practitioners. If non-scientific, non-traditional statements are included as “key point contraindications,” future generations of practitioners are going to embarrass us in the scientific community by spreading misinformation to the public.
Bob's posts lately do indeed sound like a broken record with the message of primary sources, evidence-based decisions, and critical thinking coming up again and again. But I must admit, these things are critically important for the future of our profession and the health of our patients. We want to be a serious part of the healthcare field, so it is time that we step up to the plate and act like healthcare professionals.
6 comments
Thanks a lot for this post...
Karen Vaughan
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