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MEDICAL BIOLOGY: ON THE HERBAL REMEDY ECHINACEA

The following points are made by Wallace Sampson (New Engl. J. Med. 2005 353:337):

1) How plausible are claims that echinacea, or purple coneflower, a perennial that is native to North America, is an effective treatment for viral respiratory disease? Tracing the evolution of views about the benefits of echinacea from the traditions of indigenous populations to modern claims, one finds little rationale for studying the effects of this herbal remedy on colds. Indigenous populations -- who used echinacea in various forms, including teas, local applications, and inhaled smoke --had no concept of disease states or their causes, nor could they distinguish medicinal effects from the natural course of an illness. Herbal texts list the use of echinacea by at least 13 tribes of Native Americans for the treatment of such widely diverse conditions as sore mouth and gums, cough, dyspepsia, toothache, bowel complaints, hydrophobia, and snakebite.

2) The potential for distortion of information about this herb arose between the late 1600s and the 1800s, when native people transmitted information about the uses of herbs to explorers, traders, and healers. Descriptions were translated into French, Spanish, and English and from each of those languages into others. Eventually, 19th-century physicians adopted herbs into their eclectic medicine, along with water cures, homeopathy, and manipulation. Physician H.F.C. Meyer used echinacea in his "blood purifier", a panacea for conditions ranging from migraine to wounds that were difficult to heal. More distortion probably occurred as 19th-century conditions were renamed and reclassified into modern ones.

3) Emerging as a panacea in 19th-century America, echinacea somehow became popular for the treatment of respiratory illness in Germany. In the early 1900s in the United States, echinacea was used as an "oral anti-infective" and a local application for wound healing; it then fell from favor after the introduction of antibiotics. Modern histories do not connect these trails. The supplement boom that started in the 1960s brought echinacea back to the United States as a cold remedy.

4) Between 1950 and 1991, more than 200 clinical reports of studies of echinacea appeared. Most of these were of small, inadequately controlled European studies sponsored by industry. Researchers who were looking for confirmation performed scores of in vitro studies on entire specimens of echinacea plants and on parts and extracts of plants. Positive findings included nonspecific stimulation of immune-cell division and cytokine release, but these effects have little or no correlation with clinical results. Nevertheless, advocates claimed that echinacea spurred stimulation of the immune system.

5) Turner et al [1] recently reported a randomized clinical trial of echinacea, now widely advertised as a treatment for viral respiratory disease. In a study sponsored by the National Center for Complementary and Alternative Medicine (NCCAM), the investigators tested three extracts of the root of the one species, Echinacea angustifolia, whose primary constituent group of chemicals had shown some immune-stimulating activity either in vitro or in vivo. The trial was multi-institutional, the numbers of subjects were adequate, and randomization and blinding were accomplished; the investigators used direct nasal viral challenge, a method that has been standardized and used in other trials of treatments for viral respiratory disease. So unless some obscure protocol violation occurred, the trial results are real. The clinical trial found no evidence of any clinically significant efficacy of echinacea.[2-4]

References (abridged):

1. R.B. Turner et al. New Engl. J. Med. 2005 353:341

2. Atwood KC IV. Naturopathy, pseudoscience, and medicine: myths and fallacies vs truth. MedGenMed 2004;6:33-33

3. Taylor JA, Weber W, Standish L, et al. Efficacy and safety of echinacea in treating upper respiratory tract infections in children: a randomized controlled trial. JAMA 2003;290:2824-2830

4. Skrabanek P. Demarcation of the absurd. Lancet 1986;1:960-961

New Engl. J. Med. http://www.nejm.org

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Related Material:

MEDICAL BIOLOGY: QUACK MARKETING OF INTERNET HERBAL PRODUCTS

The following points are made by C.A. Morris and J. Avorn (J. Am. Med. Assoc. 2003;290:1505-1509):

1) The Dietary Supplement Health and Education Act passed in 1994 restricted the Food and Drug Administration's (FDA's) control over dietary supplements, leading to enormous growth in their promotion.(1) Between 1990 and 1997, use of herbal remedies increased 380% in the United States.(2) Data from a 1998-1999 survey estimated that 14% of US adults took herbal supplements and approximately 1 in 5 adults taking prescription medications also used an herbal or dietary supplement.(2,3) In less than a decade, the dietary supplement industry has assumed a substantial proportion of the health market, grossing nearly $18 billion in 2001.(4)

2) The Dietary Supplement Health and Education Act and other more recent regulations(5) defined several types of labeling claims for dietary supplements. To satisfy regulatory requirements, claims that describe a relationship between a supplement and a particular condition or disease must be preapproved by the FDA and, similar to drug approval, would entail submission of evidence to substantiate the claims. In contrast, structure or function claims are not preapproved and can be made without submission of substantiating data. However, structure or function claims cannot mention specific diseases and must be accompanied by a standard disclaimer: "This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease." Only drugs can be characterized by statements about disease treatment or prevention and require more stringent FDA approval after a thorough review of available evidence concerning efficacy and safety based on randomized trials. Despite these regulations, there is growing concern in the medical community that the existing legislation inadequately protects consumers from herbal product claims.

3) Herbal products are commonly marketed on the Internet, which was used by approximately 140 million individuals in the US in 2001. According to the Pew Internet Project for Health, 62% of individuals who used the Internet in 2002 sought health information, with approximately half seeking information on alternative and complementary therapies. More than half of the Pew survey respondents said they thought "almost all" or "most" online health information they encountered was credible, and only 25% said they routinely scrutinize a health-related Web site's information, references, and sources. More than 4 of 5 Internet users used commercial search engines for their search.

4) Although the nature of Internet claims for specific products or diseases has been examined, few investigators have systematically analyzed information consumers would find through commonly used Internet search engines. The authors conducted an analysis of Internet Web sites to assess the nature of marketing claims for the 8 best-selling herbal products.

5) The authors provide the following sample disease claims from herbal product web sites:

a) Ginkgo Biloba: "Its effects in improving circulation also contribute to its use for impotency and peripheral vascular insufficiency... Ginkgo treats depression, headaches, memory loss and ringing in the ears (tinnitus). It is also recommended for Alzheimer's, asthma, eczema, heart and kidney disorders."

b) St John's Wort: "St John's wort is effective in the treatment of mild to moderate depression... recent studies have shown that it could have a potent anti-viral effect against enveloped viruses."

c) Echinacea: "Because it has natural antibiotic actions, Echinacea is considered an excellent herb for infections of all kinds. In addition, it works to boost lymphatic cleansing of the blood, enhances the immune system and has cortisone like properties which contribute to its anti-inflammatory action. It is recommended for stubborn viral infections, yeast infections and for arthritic conditions."

d) Ginseng: Q: "(I have) high blood pressure (170/90). Will American ginseng lower blood pressure and if so, how much should one take and how long before results show?" A: "While American Ginseng will help, we have a combination product that will do a much better job. Look at product #1960 American Ginseng/Garlic/Tien Chi. This is a great product... It is potentially beneficial for AIDS, radiotherapy, and chemotherapy patients, as it reduces the side effects of toxic drugs by increasing red and white blood cell counts. Dang Shen is given for breast cancer, asthma, diabetes, heart palpitations, memory or appetite loss and insomnia."

e) Saw Palmetto: "The lipophilic extract of the saw palmetto (ser repens) berries is the most widely used herbal preventive and therapeutic agent for benign prostatic hyperplasia (BPH)."

f) Kava Kava: "It is a valuable urinary antiseptic, helping to counter urinary infections and to settle an irritable bladder... Kava kava's analgesic and cleansing diuretic effect often makes it beneficial for treating rheumatic and arthritic problems such as gout."

g) Valerian Root: "The herb valerian is most effective in treating a wide range of stress conditions such as irritability, depression, fear, anxiety, nervous exhaustion, hysteria, delusions, and nervous tension... The herb is useful for treating shingles, sciatica, neuralgia, multiple sclerosis, and epilepsy."

6) The authors conclude: "Consumers may be misled by vendors' claims that herbal products can treat, prevent, diagnose, or cure specific diseases, despite regulations prohibiting such statements. Physicians should be aware of this widespread and easily accessible information. More effective regulation is required to put this class of therapeutics on the same evidence-based footing as other medicinal products."

References (abridged):

1. Dietary Supplement Health and Education Act. Pub L No. 103-417, 108 Stat 4325 (codified at 21 USC 301 [1994])

2. Eisenberg DM, Davis RB, Ettner SL, et al. Trends in alternative medicine use in the United States, 1990-1997. JAMA. 1998;280:1569-1575

3. Kaufman DW, Kelly JP, Rosenberg L, et al. Recent patterns of medication use in the ambulatory adult population of the United States. JAMA. 2002;287:337-344

4. NBJ's annual industry overview VII. Nutrition Business Journal. May/June 2002:1-48

5. US Department of Health and Human Services, US Food and Drug Administration. Regulations on statements made for dietary supplements concerning the effect of the product on the structure or function of the body; final rule, 65 Federal Register. 1000 (2000) (codified at 12 CFR 101)

J. Am. Med. Assoc. http://www.jama.com

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