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Herbal Medicines and Dietary Supplements The Hidden Dangers and Complications What is a dietary supplement? In the Dietary Supplement Health and Education Act (DSHEA) of 1994, a dietary supplement was defined as a product taken by mouth that contains a “dietary ingredient” intended to supplement the diet. The dietary ingredient may include: vitamins, minerals, herbs or other botanicals, amino acids, and substances such as enzymes, organ tissues, glandulars, and metabolites. They can be found in many forms such as tablets, capsules, gel caps, liquids or powders. DSHEA puts dietary supplements in a special category under the general umbrella of “foods,” not drugs, and requires that every supplement be labeled a dietary supplement. Facts about Dietary Supplements The U.S. Food and Drug Administration (FDA) reports that sales of herbal and botanical products totaled $3 billion dollars in 1999, representing a 20% increase from 1995. Some of the highest selling herbal products include garlic, ginseng, ginkgo biloba, and echinacea. Other common supplements include ephedra, St. John’s Wort, kava, and valerian. Clinical studies have proved some herbal supplements safe and effective, but the effectiveness of many others still hasn’t been established. Concerns regarding some popular supplements Popular herbal medications and supplements such as echinacea, ephedra, ginkgo, ginseng, kava, and St. John’s Wort may pose problems for patients during the preioperative period as well as generally have potentially serious, unwanted side effects. Another concern regarding these herbal supplements is the lack of regulation in their production and marketing, resulting in little standardization of potency and concentrations as well as exemption from the safety and efficacy requirements and regulations that prescription and over-the-counter drugs must fulfill (ie, preclinical animal studies, pre-marketing controlled clinical trials, post marketing surveillance, etc.) Popular Supplements and Potential Risks Associated With Them Echinacea Member of the daisy family, often called purple coneflower, refers to species of plants that are generally found in the Great Plains region of N. America, often used to boost the immune system and fend of the common cold and flu Has been shown to have immune-stimulating activity when administered both orally and parenterally—it increases the number of leukocytes (white blood cells) and splenocytes (white blood cells of the spleen) and enhances the activity of granulocytes (granular white blood cells) and phagocytes (cells that have the ability to ingest and destroy substances such as bacteria, protozoa, and cell debris) Concerns: Since this herb stimulates the immune system it can interfere with and diminish the effects of immunosuppressants such as cyclosporine. Thus, patients who may require preioperative immunosuppression (those awaiting organ transplantation, etc.) should be counseled to avoid or discontinue use as far in advance of surgery as possible. A history of long-term use (more than 8 weeks) could possibly increase post-surgical complications such as poor wound healing and opportunistic infections. Echinacea (Continued) Concerns (continued): Also, it can be toxic to the liver and shouldn’t be combined with other drugs that can cause liver damage, including such things as anabolic steroids and Cordarone or Pacerone (used to treat arrhythmia) Plus, it has been associated with allergic reactions, including one reported case of anaphylaxis, therefore people with asthma, atopy, or allergic rhinitis, should use it with caution. Ephedra Background: Also known as ma huang in Chinese medicine, a shrub native to central Asia Often used to promote weight loss, increase energy, and treat respiratory tract conditions such as asthma and bronchitis Contains alkaloids, including ephedrine, pseudoephedrine, norephedrine, methyephedrine, and norpseudoephedrine Concerns: Causes elevated blood pressure (hypertension) and rapid heart rate (palpitation), and these effects have been associated with more than 1070 reported adverse events including fatal cardiac and central nervous system complications (heart attacks, strokes, seizures, etc.). Therefore, users should avoid other drugs such as caffeine, decongestants, stimulants, heart drugs, and antidepressants, which mixed with ephedra can make the supplement more risky. Ephedra (Continued) Concerns (Continued): Long-term use results in tachyphylaxis from depletion of catecholamine stores and may contribute to perioperative hemodynamic instability (risk of cardiovascular collapse from the catecholamine depletion) Also, patients who have consumed ephedra and later are anesthetized with halothane may be at risk of developing intraoperative ventricular arrhythmias Due to the cardiovascular risks of ephedra (such as myocardial infarction, stroke, and cardiovascular collapse) patients taking this supplement are advised to discontinue use at least 24 hours prior to surgery. Ginkgo Background: Derived from the leaf of Ginkgo biloba Used for cognitive disorders, peripheral vascular disease, agerelated macular degeneration, vertigo Studies suggest that it may stabilize or improve cognitive performance in patients with Alzheimer disease and dementia The compounds responsible for its pharmacological effects are believed to be terpenoids and flavonoids This supplement is used by almost 11 million Americans to improve their memory and increase blood circulation Ginkgo (Continued) Concerns: Ginkgo appears to alter vasoregulation, act as an antioxidant, modulate neurotransmitter and receptor activity, and inhibit platelet-activating factor (reducing platelets which are needed for blood to clot) By reducing platelets, ginkgo presents a serious concern especially for patients undergoing surgery who, if are using ginkgo, are susceptible to an increased risk of bleeding. Therefore patients should discontinue taking ginkgo at least 36 hours prior to surgery. Also, users should avoid mixing ginkgo with such drugs as aspirin, Ticlid, Plavix, Persantine, and Coumadin, since this herb may augment the anticoagulation effect of these drugs and may cause spontaneous and excessive bleeding. Ginseng Background: Labeled an “adaptogen” since it reputedly protects the body against stress and restores homeostasis Has antioxidant, antihepatotoxic (liver-protecting), and hypoglycemic effects Wide range of possible therapeutic uses and applications with weak, debilitated, stressed or elderly people Concerns: Potential therapeutic use has to do with the herb’s ability to lower postprandial blood glucose but this effect may cause unintended hypoglycemia, especially in patients who have fasted before surgery. Also, shown to possibly inhibit platelet aggregation and prolong coagulation time. Therefore, it should not be used with warafin (Coumadin), an anticoagulant, because risk of bleeding problems increases when combined. Also, if ginseng is abused, other serious side effects can occur such as headaches, especially when mixed with phenelzine sulfate (an anti-depressant), and skin problems; therefore proper dosage for each person should be determined and followed. Other Supplements and Potential Threats Kava Often used for insomnia and short-term reduction of stress and anxiety Can be addictive and combined with sedatives, sleeping pills, alcohol, antipsychotics, and drugs to treat anxiety it can produce deep sedation and even coma, and it has been linked to 25 cases of liver toxicity (including hepatitis, cirrhosis, and liver failure) Due to the potential to an increase the effects of anesthetics as associated with the use of kava, patients should discontinue use of it at least 24 hours prior to surgery. Other Supplements and Potential Threats (Continued) St. John’s Wort (hypericum) Taken by more than 7.5 million Americans to treat anxiety, depression, and sleep disorders Reported adverse interactions between SJW and the drugs indinavir (a protease inhibitor used to treat HIV) and cyclosporine (a drug used to reduce the risk of organ transplant rejection). SJW has been shown to reduce the effectiveness of these drugs Also may intensify or prolong the effects of some narcotic drugs and anesthetic agents (can significantly increase the metabolism of some drugs), thus users should avoid mixing with any prescription medications like antidepressants Patients (especially transplant patients) are encouraged to discontinue use at least 5 days prior to surgery. Lack of Regulation: Another Source of Concern About Dietary Supplements Background: FDA regulates dietary supplements under a different set of regulations than those covering conventional foods and drugs (prescription and over-thecounter). The dietary supplement manufacturer is responsible for ensuring that a dietary supplement is safe before it is marketed, but generally manufacturers do not need to register with FDA nor get FDA approval before producing or selling a product. The FDA is responsible for taking action against any unsafe supplement after it reaches the market (must show it is unsafe before it can be pulled from the market). However, the FTC does regulate dietary supplement advertising. Lack of Regulation: (Continued) Since there is little regulation of this market, there is no standardization or enforcement on the preparation and production of these supplements, including the level of active ingredient contained in the supplement. Thus the potency of herbal medications can vary from manufacturer to manufacturer as well as from lot to lot within a manufacturer. Tests on selected herbal remedies have shown some products to contain far less or even no amounts of the active ingredient advertised, while others contained several times more of the ingredient than is specified on the label. Thus dietary supplement consumers are susceptible to being cheated or mislead as well as unknowingly taking incorrect dosages which could result in dangerous consequences, including overdosing of certain herbs which can be harmful at too high of a dosage. Lack of Regulation: (Continued) Also, plants may be misidentified or deliberately replaced with cheaper or more readily available alternatives. Herbal supplements, especially those of Eastern origin, can also be adulterated with heavy metals, pesticides, and even conventional drugs. Plus, since there is no mechanism for post-marketing surveillance (other than voluntary claims made by consumers, etc.), the incidence and exact nature of adverse reactions to herbal medications is not known or fully understood or reported. Are the problems posed by such supplements a serious threat? More than 5000 suspected herb related adverse reactions were reported to the World Health Organization before 1996. Between January 1993 and October 1998, 2621 adverse events, including 101 deaths, associated with dietary supplements were reported to the FDA. Plus, many adverse events go unreported since there is no central mechanism for mandatory reporting as this is for conventional medications and patients are sometimes reluctant to report or seek treatment for adverse reactions. What can be done? Measures that physicians can take to prevent complications Since patients may not volunteer that they are taking herbal medications in the preoperative evaluation, physicians should be assertive in inquiring about and documenting patient use of alternative medicines and supplements. Physicians should be familiar with the potential preioperative effects of the commonly used herbal supplements to prevent, recognized, and treat potentially serious problems associated with their use. They can work to have a better understanding of various herbal supplements and work to make patients more comfortable in seeking their advice so that patients make more informed decisions. Document and report cases of complications and adverse reactions in patients. What can be done? Measures that consumers can take to prevent complications Patients should follow the guidelines for discontinuing the use of some supplements before any surgeries (in general, the ASA advises patients to stop taking herbal medicines at least 2 to 3 weeks before surgery). Patients should not fear discussing herbal supplements they may be using with their doctors and should disclose any use of such productions in preoperative evaluations as well as regular check-ups. People should consult their doctor before choosing an herbal therapy or supplement. Consumers should file any complaints and adverse reactions to any supplements to the FDA’s Center for Food Safety and Applied Nutrition. Consumers can also use reputable resources on the web to research dietary supplements on their own; including the websites of such groups as the FDA and the National Institute of Health’s National Center for Complimentary and Alternative medicine which can provide information on supplements, possible complications or drug interactions, etc. Other Measures to promote safety in the use of dietary supplements More federal regulation of the production and marketing of dietary supplements? (require FDA approval before producing or selling supplements? Required warnings of possible side-effects, complications, etc. on labels of products? Etc.) Allow herbal medications to be patented? (since the inability to patent such supplements discourages manufacturers from conducting the costly research required for conventional drugs) Should some herbs be banned from being sold in the U.S. if shown to have harmful effects? How much evidence should warrant such a ban? Who will conduct this research? Other View Points and Questions Are people just too cynical and simply don’t want to admit that there are natural remedies to illnesses too? Does the government have the right to regulate the types of supplements and herbal remedies that people choose to use to treat themselves? Is there enough data to support the claims of those who say some herbal supplements pose a health risk or hazard? References “Anesthesiologists Warn: If You’re Taking Herbal Products, Tell Your Doctor Before Surgery.” American Society of Anesthesiologists. http://www.ASAhq.org/PublicEducation/herbal.html Ang-Lee, Michael K., et al. “Herbal Medicines and Perioperative Care.” Jama: Vol. 286 No. 2, July 11, 2001. “Herb and drug interactions.” MayoClinic.com. April 19, 2001. http://www.mayoclinic.com/invoke.cfm?id=SA00039 “Herbs and surgery.” MayoClinic.com. http://www.mayoclinic.com/invoke.cfm?id=SA00040 “Kava Linked to Liver Toxicity.” National Center For Complementary and Alternative Medicine. January 7, 2001. http://nccam.nih.gov/fcp/kava/kava.htm Melville, Nancy. “Bring Herbal Remedies Into Doctor Dialogue, Experts Caution.” HealthScout News. Monday, February 18, 2002. “Overview of Dietary Supplements.” U.S. Food and Drug Administration: Center for Food Safety and Applied Nutrition. January 3, 2001. http://www.cfsan.fda.gov/~dms/ds-oview.html “Public Alert on St. John’s Wort.” National Institute of Mental Health. February 20, 2001. http://www.nimh.nih.gov/events/stjohnwort.cfm Taylor, Christine. “Letter to Health Care Professionals about FDA Seeking Information on Liver Injury and Kava Products.” U.S. Food and Drug Administration: Center for Food Safety and Applied Nutrition. December 19, 2001. http://www.cfsan.fda.gov/~dms/ds-ltr27.html