51st Annual American
Academy of Family Physicians Scientific Assembly [Medscape, 1999. © 1999
Herbal Therapies Steven B. Tamarin, MD
Complementary and alternative medicine are of keen interest to patients, who
often come to their physicians with questions about the effectiveness of a
broad range of "natural" remedies. Several presentations at this
year's AAFP Scientific Assembly addressed this topic, including 2 seminars on
One presentation, by Ellen Hughes, MD, associate professor of medicine and
interim director of the Oscher Center for Integrative Medicine at the
University of California, San Francisco, was canceled
because of Hurricane Floyd. However, her handout was made available to
attendees. The other presentation was by Raul Zimmerman, MD, a clinical
assistant professor of family medicine at the University of South Florida
College of Medicine.
A Long History
Plants have been used for their medicinal value for thousands of years. Most
early medications and approximately 25% of our current
prescriptions are plant-based. Botanicals have been used as medication in this
country, although their use has been confined to rural and other discrete
areas. In Europe, notably in the United Kingdom, Germany, and Japan,
naturopathy, or the treatment of diseases using plant-based therapies, has
achieved the status of an accepted discipline. In these countries, students
are formally trained in the discipline and the quality of herbal medications
is regulated as much as we monitor pharmaceuticals in this country.
Scope of Use
Americans spent more than $4 billion on herbal medications in 1997.[3,4] It is
estimated that in 1993, 60 million Americans used alternative therapies at a
cost of $13.7 billion. Many of these patients use herbal preparations in
addition to prescription drugs; approximately 70% never mention it to their
Whether or not physicians believe that herbals have value, patients are using
them. The AAFP presentations underlined the need, therefore, to be informed
about the risks, benefits, interactions, and science related to the use of
Are Herbal Therapies Safe?
A question raised in both presentations was whether herbal preparations are
safe and effective. Prior to 1994, herbs were in a "nether" category
between medication, which is regulated by the Food and Drug Administration
(FDA) for safety and efficacy, and food, which is regulated for manufacturing
standards and safety. Herbals were not consistently in either category and so
the FDA proposed to regulate food supplements including herbals.
A public relations campaign by the supplement industry followed, which
included deluging Congress with 4 million letters and faxes and commercials
portraying FDA supplement policy as overly harsh. Thus, the Dietary Supplement
Health and Education Act of 1994 was passed. This law classifies vitamins,
minerals, herbs, and amino acids as dietary supplements and frees their
manufacturers from having to test for or prove safety, efficacy, or standards
In fact, the FDA must prove that a product is unsafe. This has led to several
examples of how consumers have been put at risk by use of certain supplements.
One example was the contaminated L-tryptophan that caused fatalities related
to the eosinophilic-myositis syndrome. There also have been reports of
intentional contamination by analgesics, steroids, and sedatives and other
undeclared prescription medications
for a more dramatic effect.[6,7]
So where does that leave the physician who would like to recommend botanical
remedies to patients that prefer them to medications with known adverse
It has been widely assumed that there is no science to support the use of
herbals as medications. Until recently, the literature indeed has been scarce,
particularly with regard to solid clinical studies. In
fact, now there is a large body of European and Japanese literature that
assesses the medical use of a number of herbals.
One of the most useful compilations is the Report of the German E Commission,
recently translated, and now published in English by the American Botanical
Council 1997. This commission included physicians, pharmacists,
toxicologists, and botanists, who wrote approximately 400 monographs between
1978 and 1994. They evaluated the available data and determined whether there
was reasonable certainty of the safety and efficacy of the medicinal use of
the plants studied. They also established standard preparations and doses.
In the US, Congress has created the National Center for Complementary and
Alternative Medicine, which is translating data and coordinating study
centers throughout the United States to review a variety of areas. Another
useful source of information is the US Department of Agriculture's
phytochemical and ethnobotanical database. Increasingly, studies of herbal
preparations and their effectiveness -- or lack thereof -- are being published
in peer-reviewed medical journals.
The speakers at the AAFP meeting reviewed the clinical use of the most popular
herbs with data supporting their use as well as underscoring the need for
Dr. Zimmerman discussed some well-documented drug-herb interactions.
Nonsteroidal anti-inflammatory drugs may negate feverfew, for example,
echinacea can potentiate the toxicity of hepatotoxic drugs, and ginkgo,
ginger, and ginseng should not be used with coumadin due to their
Citing a poll in Good Housekeeping Magazine and data from herbal
manufacturers, Dr. Zimmerman cited the most popular herbs now in use:
ginseng, garlic, ginkgo biloba, echinacea, St. John's wort, goldenseal, saw
palmetto, aloe, Siberian ginseng, pycnogenol/grapseed extract, and evening
One of the most popular and widely used herbs is St. John's wort, which is
reported to be effective for mild to moderate depression and to have few
adverse effects. The dose is 300 mg 3 times daily as .3%
Ginkgo biloba has recently become popular following reported modest
improvement of cognitive functioning in some people with dementia caused by
Alzheimer disease or cerebrovascular disease. In addition, ginkgo is used for
sexual dysfunction caused by selective serotonin reuptake inhibitors and in
peripheral vascular disease. The dose range is 80 to 240 mg/day 2 or 3 times
Kava kava is used for anxiety, insomnia, and muscle tension, but there is
concern regarding drug and alcohol interactions, and a yellow scaly rash has
been reported at high doses (>9 g/day). The dose is 100 mg 3 times daily of
kava extract WS 1490.
Studies indicate that saw palmetto is safe and effective for the symptoms of
benign prostatic hyperplasia. The usual dose is 160 mg of standardized extract
containing 85% to 95% fatty acids and sterols (Permixon) 3 times daily. The
main adverse effects are gastrointestinal.[18,19,20]
Echinacea is used for short-term treatment and prevention of respiratory
infections. There are numerous preparations and doses.[21,22] Some data
support the use of milk thistle as a liver protective in mild cases of
Garlic is used to improve lipids and hypertension.[24,25]
Feverfew is used for the prophylaxis of migraine and cluster headaches.
Finally, ginger is used as an antiemetic, especially in pregnancy.
As more data regarding the safety and efficacy of herbal preparations become
available, especially in the prestigious peer-reviewed literature, and as more
standardized preparations from reputable manufacturers come to the market,
perhaps physicians will be in a more comfortable position to inform patients
about the appropriate use of botanical medicinals.
Hughes E. Botanicals: what are your patients taking? Programs and abstracts
from the 1999 Scientific Assembly of the American Academy of Family
Physicians; September 16-19, 1999; Orlando, Fla. Abstract 503.
Zimmerman RL. Herbal therapies: new for 1999. Programs and abstracts from the
1999 Scientific Assembly of the American Academy of Family
Physicians; September 16-19, 1999; Orlando, Fla. Abstract 033.
Astin JA. Why patients use alternative medicine: results of a national study.
Johnston B. One-third of nation's adults use herbal remedies: market estimated
at $3.24 billion. Herbalgram. 1997;40:49.
Ko RJ. Adulterants in Asian patent medicines. N Engl J Med.
Gertner E, Marshall PS, Filandrinos D, Potek AS, Smith TM. Complications
resulting from the use of Chinese herbal medications containing undeclared
prescription drugs. Arthritis Rheum. 1995;38:614-617.
Slifman NR, Obermeyer WR, Aloi BK, et al. Contamination of botanical dietary
supplements by Digitalis lanata. N Engl J Med. 1998;339:806-811.
Blumenthal M, Busse WR, eds. Klein S, trans. German Commission E
Monographs. Austin, Tex: American Botanical Council; 1997.
Available at: http://altmed.od.nih.gov.
Available at: www.ars-grin.gov/duke.
O'Hara MA, Kiefer D, Farrell K, Kemper K. A review of 12 commonly used
medicinal herbs. Arch Fam Med. 1998;7:523-536.
Varro T. Herbs of Choice: The Therapeutic Use of Phytochemicals. New York, NY:
Pharmaceutical Products Press; 1994.
Miller L. Herbal medicinals: selected clinical considerations focusing on
known or potential drug-herb interactions. Arch Intern Med.
Cupp ML. Herbal remedies: adverse effects and drug interactions. Am Fam
Linde K, Ramirez G, Mulrow CD, Pauls A, Weidenhammer W, Melchart D. St. John's
wort for depression; an overview and meta-analysis of randomized clinical
trials. BMJ. 1996;313:253-258.
Le Bars PL, Katz MM, Berman N, Itil TM, Freedman AM, Schatzberg AF, and the
North American EGb Study Group. A placebo-controlled, double-blind randomized
trial of an extract of Ginkgo biloba for dementia. JAMA.
Volz HP, Kieser M. Kava-kava extract WS1490 versus placebo in anxiety
disorders: a randomized placebo-controlled 25-week outpatient trial.
Carraro, JC et al. Comparison of phytotherapy (Permixon) with finasteride in
the treatment of benign prostate hyperplasia: a randomized international study
of 1,098 patients. Prostate
Wilt TJ, Ishani A, Stark G, MacDonald R, Lau J, Mulrow C. Saw palmetto
extracts for treatment of benign prostatic hyperplasia: a systematic review.
Lowe FC, Ku JC. Phytotherapy in treatment of benign prostatic hyperplasia: a
critical review. Urology. 1996;48:12-20.
Melchart D, Linde K, Worku F, et al. Results of five randomized studies on the
immunomodulatory activity of preparations of echinacea. Altern Complement Med.
Melchart D, Linde K. The Cochrane Collaboration Database of Systematic
Reviews. Jan 1999. Available at:
Flora K, Hahn M, Rosen H, Benner K. Milk thistle (Silybum marianum) for the
therapy of liver disease. Am J Gastroenterol. 1998;93:139-143.
Isaacsohn JL, Moser M, Stein EA, et al. Garlic powder and plasma lipids and
lipoproteins: a multicenter, randomized, placebo-controlled trial.
Arch Intern Med. 1998;158:1189-1194.
Berthold HK, Sudhop T, von Bergmann K. Effect of a garlic oil preparation on
serum lipoproteins and cholesterol metabolism: a randomized controlled trial.
Murphy JJ, Heptinstall S, Mitchell JR. Randomised double-blind
placebo-controlled trial of feverfew in migraine prevention. Lancet.
Aikins Murphy P. Alternative therapies for nausea and vomiting of pregnancy.
Obstet Gynecol. 1998;91:149-155.
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