Herbal supplement interactions with prescription meds for “heart problems”

"Heart attack" (get it?). iStockphoto via CBS News

...or, "how to artificially inflate your readership." Yesterday, I saw tweets about a CBS News online article - or so I thought - about 30 herbal dietary supplements to avoid if one has "heart trouble." What I found was a photo gallery site that I had to click on 20 times to obtain the information - an adaptation of this paper from Mayo Clinic Rochester and Scottsdale investigators in the Journal of the American College of Cardiology last February. Most of the herbs listed were there because of their positive or negative interactions with the oral anticoagulant drug, warfarin. This list included typical, top-ranked supplements such as ginkgo, garlic, saw palmetto, green tea, and alfalfa. Granted, each page had a lovely photo of the plant or product and a brief description. The list also included herbs that acted via other mechanisms such as St. John's wort, which can accelerate the metabolism of a wide variety of drugs (via CYP3A4 induction) and yohimbine, whose alpha-2 receptor antagonistic activity can modify the effects of prescription antihypertensive drugs. The information actually appears quite valid and, from my knowledge of the literature, appears quite accurate. Of course, it doesn't include original literature references since the gallery appears intended for a general readership. But I found it vexing to have to click through 20 pages - also after being misled into clicking the only hyperlink in the frontpage of the photo gallery, CBS News' "friends" at Health.com (link not provided here on purpose), thinking that it was the source of the "easy guide." Or maybe I'm just cranky because I have figured out a way to get you to click on my site here 20 consecutive times. Reference: Tachjian, A., Maria, V., & Jahangir, A. (2010) Use of Herbal Products and Potential Interactions in Patients With Cardiovascular Diseases. Journal of the American College of Cardiology, 55(6), 515-525. DOI: 10.1016/j.jacc.2009.07.074

Author: David Kroll

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  1. I can press refresh 20 times to make you feel better?

  2. The paper link is returning an URL format error. Can we have the old style citation so we can look it up?

  3. @antipodean – Heh. Although we’re not driven by traffic-associated ad revenue here, there’s still a little bit of me that derives personal value from the readership. But you needn’t click 20 times to make me happy – simply leaving a comment is sufficient for my self-validation.

    @DaveH – Thanks so much for pointing out the broken link. I fixed the link but also added the old-fashioned reference to the post together with the DOI.

  4. I saw this article and was also upset with it, because I kept clicking around and around and around trying to see if it would say anything about dosage. Are they telling people to avoid garlic-y sauces and a cup of tea, or what? Without dosage information, I don’t see this information as that helpful.

    You told antipodean not to refresh 20 times, I assume you also don’t want 40 comments in a row from me. Feel self validated, anyway.

  5. It occurs to me that for actual heart patients, the imagery here might be too disquieting to be effective at conveying the underlying information.

  6. To be honest, Gaythia, comments are much more like blogger crack for me than are pageviews. For example, I wrote a post Friday for my monthly gig at Science-Based Medicine that drew over 4,000 pageviews but, alas, only two comments. I got into blogging to have a conversation so please comment all you’d like! I’d much rather have every one of 20 readers leave a comment!

    Indeed, for those herbs with culinary use the CBS News feature could be very disconcerting. I’m reminded of the confusion over soy in women with estrogen-dependent breast cancer. While genistein and other isoflavones can support ER-dependent breast carcinoma growth, they’re probably only a problem with highly-concentrated soy supplement – not typical amounts of compounds in tofu or other soy-based food products. (Correct me if I’m wrong.)

    • Dave, I found your recent post at SBM interesting and self-contained. No need to comment- until I replied to some other comments. You may not have sparked the discussion you wanted; but the comments are mounting. The link for those interested:


      • Thanks very much – funny but after I only got 2 comments on Friday, I didn’t think to stop back to see if any discussion ensued. I get e-mail pings when comments come here to Terra Sig and over at Take As Directed but I’m not set up for that at SBM.

  7. @JJM and David Kroll; I doubt that the direction of the discussion that ensued probably will make either one of you (or Dr. Atwood) supporters of this New Scientist proposal below, and I assume JJM (Joe?) is going to try to have you working on that blogger crack addiction. But now I understand why you didn’t weigh in. I would agree with JJM above that the original post was complete and self contained.

    Time to Democratize Science

    Can you see this working out well?

    “Certainly the public will sometimes support research that seems fanciful to informed insiders. We won’t always spend our money wisely. But the opportunity to exercise power is a great educator. The successes and failures of democratically funded science would promote a much more vigorous public debate about the purpose of research.”

    And perhaps the discussion on the SBM site will inspire some future posts from you such as on the philosophy and history of science and how that relates to the biochemistry and pharmacology of natural products. Personally, I think that there is room to navigate between “anthro’s” real concerns about the field of Anthropology’s abandonment of science in favor of treating each culture with respect and without scientific judgment and seemingly making the admittedly huge strides forward of the primarily European Scientific Revolution of the 1700’s into a defined line between science and not science.