Astin criticizes authors of several papers in the March 2001 special set for failing to offer what he believes would represent a more “balanced” view of complementary and alternative medicine (CAM).1 In responding to similar criticism by Sierpina and Philips,2 I re-emphasized the critical role that scientific evidence must play in evaluating safety and efficacy of therapeutic interventions, while noting the lack of compelling evidence for efficacy, safety, and outcomes of CAM therapies.3 I comment now on Astin's article, focusing on the important question he poses regarding CAM safety.
Astin supports the central points made by the authors he criticizes, agreeing that “evidence-based answers as to whether a given therapy is or is not effective is of vital importance in investigating CAM” and stating that “in cases where people are using demonstrably inefficacious or unsafe therapies, such choices represent unsound, irrational, or uncritical thinking.” He notes correctly that “human beings frequently fall prey to fantastic claims of healing, weight loss, etc., based upon little if any credible evidence.” Like the authors of the special set, he “would personally love to see the public become more thoughtful, reflective, and critical of what they read … and hear in the media about how to care for their health.”
Interestingly, Astin circumvents such critical thinking when he chides Sampson, Marcus, Beyerstein, and me for citing data that fail to support his view of the potential value of CAM and for not providing specific references. Despite his implications, however, all statements made in the several articles that he criticizes are abundantly supported by original research reports published in leading scientific journals. In contrast, Astin relies almost exclusively on meta-analyses and reviews to support his claims for effectiveness of various herbal remedies, homeopathy, and therapeutic touch.1 Although meta-analysis may be a useful tool for discarding poorly controlled studies, as a purely statistical analysis applied to observational studies it is prone to various biases4 and can never replace properly designed, randomized, clinical trials. Such “gold standard” studies include a recent NIH-funded trial demonstrating equivalence of placebo and St. John's wort in the treatment of clinical depression5 and the simple, inexpensive, but well-controlled study describing failure of the sine-qua-non principle of therapeutic touch.6
Dr. Astin asks “Which specific [CAM] therapies are dangerous?” Herbal remedies, the most common form of alternative medicine, provide a wealth of examples. For a review of the recent literature, Astin should consult “Harmless Herbs?,”7 written by E. Ernst, co-author of five of the ten reviews cited in support of herbal remedies Astin believes to be efficacious.1 In 2001, reports to U.S. poison control centers of adverse effects of herbals and other dietary supplements reached 19,468, up from 6,200 in 1998.8 Kava, which Astin calls effective in the treatment of anxiety, has been banned in many European countries, but not in the United States, due to its hepatic toxicity. Aristolochia fangchi, used in Europe and Asia for 2000 years, is highly nephrotoxic and carcinogenic.9 Adulteration of Asian herbal medicines with prescription drugs and dangerous substances, including toxic metals,10 is common practice,11 and the reported efficacy of yohimbine for erectile dysfunction cited by Astin,1 as well as claims for other herbal aphrodisiacs, may simply reflect the presence of Viagra surreptitiously added to these products. Most alarming is the finding that the “effective” mixture of herbs used to treat prostate cancer under the name PC-SPES is routinely adulterated with diethylstilbesterol, warfarin, and indomethacin, accounting for its biologic effects.12
Still another herbal remedy, ephedra (ma huang), used for millennia in traditional Chinese medicine, has been widely adopted in the United States as an “energy pill” and as the mainstay of weight reduction programs. More than 1,000 serious toxic reactions to ephedra, including cardiac arrhythmias, hypertension, psychosis, seizures, and deaths, have been reported (voluntarily) to the FDA.13 Over half these events occurred in persons less than 40 years of age. An independent study revealed that the FDA records less than 1% of the total number of adverse events resulting from dietary supplements.14 Thus, it is estimated that over a relatively short period of time, more than 100,000 American consumers suffered serious adverse effects from ephedra.
Possibly the greatest health risk posed by herbal medicines involves their significant potential for interaction with prescription drugs. For example, St. John's wort, widely used in the United States and Europe to treat depression, is metabolized by the same biochemical pathway as almost half of the prescription drugs administered for the treatment of hypertension, heart failure, asthma, and AIDS. Taken alone, St. John's wort is relatively innocuous, but when used in combination it has been shown to rapidly render these life-saving drugs ineffective.15,16 Currently, one in six patients taking prescription drugs also takes one or more herbals/supplements17; as a result, reports of drug—herb interactions are certain to increase.
In conclusion, it appears that the “unsafe CAM therapies” deplored by Astin1 are exemplified by herbal medicines in common use. His question, to which I have responded, underscores the pervasive tendency of CAM supporters to ignore or downplay well-documented dangers of CAM therapies and exposes the Achilles' heel of alternative medicine. The scope of this significant public health problem could be sharply reduced simply by mandating premarketing safety testing for herbal remedies and requiring manufacturers to report all adverse drug reactions to the FDA.18 Such action would require that Congress amend the 1994 Dietary Supplement Health and Education Act, legislation that allows herbal medicines labeled as dietary supplements to be marketed without chemical analysis or prior testing for safety. Apparently, the vast majority of Americans support such a change.19
1. Astin JA. Complementary and alternative medicine and the need for evidence-based criticism. Acad Med. 2002;77:864–8.
2. Sierpina VS, Philips B. Need for scholarly, objective inquiry into alternative therapies. Acad Med. 2002;76:863–4.
3. Grollman AP. In reply. Acad Med. 2001;76:864–5.
4. Stroup DF, Berlin JA, Morton SC, et al. Meta-analysis of observational studies in epidemiology, a proposal for reporting. JAMA. 2000;283:2008–12.
5. Hypericum Depression Trial Study Group. Effect of Hypericum perforatum
(St. John's wort) in major depressive disorder; a randomized controlled trial. JAMA. 2002;287:1807–14.
6. Rosa L, Rosa E, Sarner L, Barrett S. A close look at therapeutic touch. JAMA. 1998;279:1005–10.
7. Ernst E. Harmless herbs? A review of the recent literature. Am J Med. 1998;104:170–8.
8. Litovitz TL, Klein-Schwartz W, Rodgers GC, et al. 2001 Annual report of the American Association of Poison Control Centers Toxic Exposure Surveillance System. Am J Emerg Med. 2002;20(Sept).
9. Kessler DA. Cancer and herbs. N Engl J Med. 2000;342:1742–3.
10. Ernst E. Toxic heavy metals and undeclared drugs in Asian herbal medicines. Trends Pharmacol Sci. 2002;23:136–9.
11. Ko RK. Adulterants in Asian patent medicines. N Engl J Med. 1998;339:847.
12. Sovak M, Seligson AL, Konas M, et al. PC-SPES in prostate cancer: an herbal mixture currently containing warfarin and previously diethylstilbestrol and indomethacin. Proc Am Assoc Cancer Res. 2002;Abstr LB152.
13. Haller CA, Benowitz NL. Adverse cardiovascular and central nervous system events associated with dietary supplements containing ephedra alkaloids. N Engl J Med. 2000;343:1833–8.
14. Adverse Event Reporting for Dietary Supplements: An Inadequate Safety Valve: Report from Department of Health and Human Services: Office of the Inspector General. 2001(April), OEI-01-00-00180.
15. Piscitelli SC, Burnstein AH, Chaitt D, et al. Indinavir concentrations and St. John's wort. Lancet. 2000;355:547–8.
16. Ruschitzka F, Meier PJ, Turina M, et al. Acute heart transplant rejection due to St. John's wort. Lancet. 2000;355:548–9.
17. Kaufman DW, Kelly JP, Rosenberg L, Anderson TE, Michell AA. Recent patterns of medication use in the ambulatory adult population of the United States: the Sloane Survey. JAMA. 2002;287:337–44.
18. Testimony of Arthur P. Grollman, MD, before the White House Commission on Alternative Medicine Policy, May 15, 2001. 〈www.whccamp.hhs.gov/
〉. Accessed 6/01/02.
19. Blendon RJ, DesRoches CM, Benson JM, et al. Americans' views on the use and regulation of dietary supplements. Arch Intern Med. 2001;161:805–10.