Herbal Medicines and Perioperative Care
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REVIEW Herbal Medicines and Perioperative Care Michael K. Ang-Lee, MD Context Widespread use of herbal medications among the presurgical population Jonathan Moss, MD, PhD may have a negative impact on perioperative patient care. Chun-Su Yuan, MD, PhD Objectives To review the literature on commonly used herbal medications in the context of the perioperative period and provide rational strategies for managing their HERE IS ENORMOUS PUBLIC EN- preoperative use. thusiasm for herbal medica- Data Sources The MEDLINE and Cochrane Collaboration databases were searched tions. Two recent surveys have for articles published between January 1966 and December 2000 using the search terms found widespread use among herbal medicine, phytotherapy, and alternative medicine and the names of the 16 Tthe presurgical population.1,2 Morbid- most commonly used herbal medications. Additional data sources were obtained from ity and mortality associated with herbal manual searches of recent journal articles and textbooks. medications may be more likely in the Study Selection We selected studies, case reports, and reviews addressing the safety perioperative period because of the and pharmacology of 8 commonly used herbal medications for which safety informa- polypharmacy and physiological alter- tion pertinent to the perioperative period was available. ations that occur.3 Such complica- Data Extraction We extracted safety, pharmacodynamic, and pharmacokinetic infor- tions include myocardial infarction, mation from the selected literature and reached consensus about any discrepancies. stroke, bleeding, inadequate oral anti- Data Synthesis Echinacea, ephedra, garlic, ginkgo, ginseng, kava, St John’s wort, coagulation, prolonged or inadequate and valerian are commonly used herbal medications that may pose a concern during anesthesia, organ transplant rejection, the perioperative period. Complications can arise from these herbs’ direct and phar- and interference with medications in- macodynamic or pharmacokinetic effects. Direct effects include bleeding from garlic, dispensable for patient care. ginkgo, and ginseng; cardiovascular instability from ephedra; and hypoglycemia from Of the herbal medications that cli- ginseng. Pharmacodynamic herb-drug interactions include potentiation of the seda- tive effect of anesthetics by kava and valerian. Pharmacokinetic herb-drug interac- nicians are likely to encounter, we have tions include increased metabolism of many drugs used in the perioperative period by identified 8 of the herbs that poten- St John’s wort. tially pose the greatest impact to the care of patients undergoing surgery. These Conclusions During the preoperative evaluation, physicians should explicitly elicit and document a history of herbal medication use. Physicians should be familiar with herbs account for more than 50% of all the potential perioperative effects of the commonly used herbal medications to pre- single herb preparations among the vent, recognize, and treat potentially serious problems associated with their use and 1500 to 1800 herbal medications sold discontinuation. 4,5 in the United States. Nonherbal di- JAMA. 2001;286:208-216 www.jama.com etary supplements, such as vitamins, minerals, amino acids, and hormones, medications as they affect periopera- desirable effects. Our goal is to pro- are beyond the scope of this review. tive care; and propose rational strate- vide a framework for physicians prac- Some of these nonherbal dietary supple- gies for managing the preoperative use ticing in the contemporary environment ments that patients undergoing sur- of these agents. The prevention, rec- where widespread herbal medicine use gery are most likely to take, such as ognition, and treatment of complica- occurs. glucosamine and chondroitin for os- tions begin with explicitly eliciting and 6,7 teoarthritis, appear to be safe. Lim- documenting a history of herbal medi- Author Affiliations: Department of Anesthesia and ited information is available, how- cine use. Familiarity with the scien- Critical Care (Drs Ang-Lee, Moss, and Yuan), Tang Center for Herbal Medicine Research (Dr Yuan), and ever, on the use of these supplements tific literature on herbal medications is Committee on Clinical Pharmacology (Dr Yuan), The in the presurgical population. necessary because the current US regu- Pritzker School of Medicine, University of Chicago, Chi- cago, Ill. In this article, we consider safety and latory mechanism for commercial Corresponding Author and Reprints: Chun-Su Yuan, US regulatory issues for herbal medi- herbal preparations sold in the United MD, PhD, Department of Anesthesia and Critical Care, University of Chicago, 5841 S Maryland Ave, MC 4028, cations; review the literature on the States does not necessarily protect the Chicago, IL 60637 (e-mail: [email protected] identified 8 commonly used herbal population against unpredictable or un- .edu). 208 JAMA, July 11, 2001—Vol 286, No. 2 (Reprinted) ©2001 American Medical Association. All rights reserved. Downloaded from www.jama.com at Johns Hopkins University, on October 28, 2005 HERBAL MEDICINES AND PERIOPERATIVE CARE Preoperative Use Drug Administration to show that a cians do not always recognize adverse of Herbal Medications product is unsafe before it can be re- events associated with herbal medica- The most extensive surveys on the moved from the market.14 In addition, tion use34 and that patients are reluc- use of complementary and alternative the inability to patent herbal medica- tant to report and seek treatment for the medicine use in the United States tions discourages the manufacturers adverse reactions.35 This reluctance has revealed that approximately 12% of from performing the costly research re- been attributed to the belief that physi- the population used herbal medica- quired for conventional drugs.15 cians cannot be consulted in the use of tions in 1997,8,9 representing a 380% The current US regulatory mecha- unconventional therapies and that increase from 1990. Patients undergo- nism provides little assurance that com- patients are unwilling to admit the use ing surgery appear to use herbal mercial herbal preparations have pre- of these remedies to physicians. The defi- medications significantly more fre- dictable pharmacological effects and ciencies in monitoring adverse events for quently than the general population. that product labels provide accurate in- herbal medicines mean that safety pro- For instance, Tsen et al1 reported that formation. The potency of herbal medi- files are usually limited to animal stud- 22% of patients who underwent cations can vary from manufacturer to ies, case reports, or predictions derived evaluation in their preoperative clinic manufacturer and from lot to lot within from known pharmacological results. took herbal medications. Also, Kaye et a manufacturer.16-18 Plants may be al2 found that 32% of patients in an misidentified or deliberately replaced METHODS ambulatory surgery setting admitted with cheaper or more readily available We identified the most commonly used to using herbal medications. alternatives.19-22 Moreover, herbal medi- herbal medications by 1999 sales data More than 70% of the patients in the cations, especially those of Eastern ori- and surveys in the literature.1,2,4 The study by Kaye et al2 failed to disclose gin, can be adulterated with heavy met- MEDLINE and Cochrane Collabora- their herbal medicine use during als, pesticides, and even conventional tion databases were searched for ar- routine preoperative assessment. Ex- drugs.23-25 Some herbal manufacturers ticles published between January 1966 planations for this lack of disclosure in- have tried to standardize their herbal and December 2000, using the search clude patient-held beliefs that physi- products to fixed concentrations of se- terms herbal medicine, phytotherapy, al- cians are not knowledgable about herbal lected chemical constituents.26 The ben- ternative medicine, and the names of the medications or are prejudiced against efit of this effort is uncertain, how- most commonly used herbal medica- their use.10 Some patients may fear ad- ever, because many products achieve tions (aloe, bilberry, cascara, cranberry, mitting to their physicians their use of their effects through the combined or echinacea, ephedra, garlic, ginseng, ginkgo, unconventional therapies.11 Others may synergistic actions of different com- goldenseal, kava, milk thistle, saw pal- neglect to mention that they are tak- pounds.27 Even when advertised and la- metto, soy, St John’s wort, and valerian). ing herbal medications when they are beled as standardized, potency can still Additional sources included manual using them for reasons perceived as un- vary considerably.28 searches of textbooks and recent sur- related to their medical care.12 Still other Because there is no mechanism for gery, anesthesiology, and alternative patients would not consider these sub- postmarketing surveillance, the inci- medicine journals. stances to be medications, and they may dence and exact nature of adverse events Although we found no randomized neglect to report them during routine is unknown. Empirical evidence gained controlled trials that evaluated the ef- preoperative questioning. For these rea- from a long history of herbal medica- fects of prior herbal medicine use on the sons, it is necessary for physicians to tion use supports the notion that most perioperative period, we identified, specifically seek out a history of herbal are safe.29 Nevertheless, some of these based on our