Use of herbal supplements is increasingly common in the U.S. Since Congress de-regulated such supplements in 1994, manufacturers are no longer required to report adverse reactions to these preparations to any agency. However, commonly used herb drugs may cause problems in patients during and after surgery. Physicians should be aware of potential side effects of herbal medications and should obtain a complete history of herbal medication use from their patients before a scheduled surgery, according to an article in the July 11 issue of The Journal of the American Medical Association.
Michael K. Ang-Lee, M.D., and colleagues from the Pritzker School of Medicine, University of Chicago, identified commonly used herbal supplements based on 1999 sales data and surveys. The herbal medications analyzed in this study were ephedra, echinacea, garlic, ginseng, ginkgo, valerian, kava and St. John’s wort. The authors then searched for and reviewed articles published between 1966 and 2000 on the safety, effect, and action of these herbs to determine if they may have a negative impact on patients who undergo surgery, during the period of time surrounding the procedure.
Studies have shown that approximately 12 percent of the U.S. population uses herbal medications, and 22 percent of patients scheduled for surgery reported using such medications. The eight herbal medications studied account for more than fifty percent of all herb preparations sold in the U.S.(the article does not include data on nonherbal supplements such as vitamins, minerals, amino acids and hormones).
According to previous studies, possible complications from use of herbal medications include heart attack, stroke, bleeding, increased or decreased effectiveness of anesthesia, transplant rejection, and interactions with other medications. The effects of some herbal medications can linger two to three weeks after patients stop using them.
In this study, the authors found that the herbal preparations analyzed may pose a concern before, during, or after surgery. Direct effects include bleeding from ginkgo, garlic and ginseng; irregularities in heart rate from ephedra. Valerian and kava may interact with anesthetics, provoking a greater depressive effect of anesthetics on blood pressure and respiration. Possible effects of St. John’s wort include altered metabolism of many drugs used in the period around an operation.
Previous research suggests that patients may withhold information about their herbal medication use from their physicians for various reasons.
There is no mandatory reporting for adverse events in herbal medication use, which is contrary to conventional medication mandates.
Tags: herbal medications, minerals, surgery