ABC Responds to Article on Herb-Drug Interactions in Journal of the American College of Cardiology

(Austin, TX) At least several times per year an article is published in a medical journal that purports to provide health professionals and the public with useful information on the safety of herbs and herbal dietary supplements. Instead, what sometimes occurs is an article written by people with apparently little to no expertise in the subject area of herbal medicine and medicinal plant research and likewise apparently peer reviewed—if peer reviewed at all—by reviewers with little botanical knowledge or expertise. Yesterday, the Journal of the American College of Cardiology published such an article.1

This particular article has so many flaws and errors that it is difficult to know where to begin to critically review it.

First, Latin names for the herbs discussed are missing, a disservice to any readers who may not be familiar with common names used in the United States.

Second, some of the tables in the article contain entries for “commonly used herbs,” which include the toxic plant oleander (Nerium oleander, a toxic herb with cardioactive glycosides not sold to consumers in the US dietary supplement market); chan su (presumably dried Chinese toad venom—not an herb nor generally available as a dietary supplement!); and uzara root (Xysmalobium undulatum), an anti-diarrhea herbal drug approved in Germany. None of these are “commonly” found in the US herbal dietary supplement market.

Grapefruit juice, which is well known for increasing serum levels of many pharmaceutical drugs, is referred to as an herb.

The authors refer to “ginseng” without clarifying which species of the genus Panax they are referring, many of which cause varying pharmacological effects. Also, with respect to “ginseng,” the authors unfortunately repeat the highly erroneous adverse effect information from the widely discredited 1979 uncontrolled study by RK Siegel on the “Ginseng Abuse Syndrome,” stating that “ginseng” can cause “hypertension, behavioral changes and diarrhea.”

Capsicum is listed in a table as being used for shingles, trigeminal, and diabetic neuralgia, when it is actually the US Food and Drug Administration-approved over-the-counter and prescription drug capsaicin, the vanillanoid compound derived from chili peppers (Capsicum spp.), which is used for such purposes.

There are more; the errors and problems in this paper are too numerous to list completely at this time.

While there are potential and actual interactions that various herbs can have with drugs used by patients with cardiovascular diseases, this paper will do little to improve professional awareness and skill in this area. However, the resulting media coverage will undoubtedly increase public confusion over what is an already confused subject. This paper should not have been published in its present form without serious additional edits, revisions, and deletions, and the Journal of the American College of Cardiology would be advised to retract it.

Reference

Tachjian A, Maria V, Jahangir A. Use of herbal products and potential interactions in patients with cardiovascular diseases. J Amer Coll Cardiol. 2010;55(6). [DOI:10.1016/j.jacc.2009.07.074].