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Photo copyright Steven Foster
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Botanical name: Astragalus membranaceus
Parts used and where grown: Astragalus is native to northern
China and the elevated regions of the Chinese provinces, Yunnan and Sichuan. The portion of
the plant used medicinally is the four- to seven-year-old dried root, collected in the spring.
While over 2,000 types of astragalus exist worldwide, the Chinese version has been extensively
tested, both chemically and pharmacologically.1
Astragalus has been used
in connection with the following conditions (refer to the individual
health concern for complete information):
Historical or traditional use (may or may not
be supported by scientific studies): Shen Nung, the founder of Chinese herbal
medicine, classified astragalus as a superior herb in his classical treatise Shen Nung Pen
Tsao Ching (circa A.D. 100). The Chinese name huang qi translates as
“yellow leader,” referring to the yellow color of the root and its status as one
of the most important tonic herbs. Traditional Chinese
Medicine used this herb for night sweats, deficiency of chi (e.g., fatigue, weakness, and
loss of appetite), and diarrhea.2
Active constituents: Astragalus contains numerous components,
including flavonoids, polysaccharides, triterpene
glycosides (e.g., astragalosides I–VII), amino
acids, and trace minerals.3 Several preliminary clinical trials in China have
suggested that astragalus can benefit immune
function and improve survival in some people with
cancer.4 Given the poor quality of these trials, it is difficult to know how
useful astragalus really was. One Chinese trial also found that astragalus could decrease
overactive immune function in people with systemic lupus
erythematosus (SLE), an autoimmune disease.5 Further trials are needed,
however, to know if astragalus is safe for people with SLE, or any other autoimmune
disease.
A double-blind trial found that, in people undergoing dialysis for kidney failure,
intravenous astragalus improved one facet of immune function compared to the immune function
of untreated people.6 Further study is needed to determine if astragalus can help
prevent infections in people undergoing dialysis. Early
clinical trials in China suggest astragalus root might also benefit people with chronic viral
hepatitis, though it may take one to two months to see
results.7
In preliminary trials in China, astragalus has been used after people suffer heart attacks.8 More research is needed to
determine whether astragalus is truly beneficial in this situation.
How much is usually taken? Textbooks on Chinese herbs
recommend taking 9–15 grams of the crude herb per day in decoction form.9 A
decoction is made by boiling the root in water for a few minutes and then brewing the tea.
Alternatively, 3–5 ml of tincture three times per day, are sometimes recommended.
Are there any side effects or interactions? Astragalus has no
known side effects when used as recommended.
At the time of writing, there were no well-known drug interactions
with astragalus.
References:
1. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients
Used in Food, Drugs, and Cosmetics, 2d ed. New York: John Wiley & Sons, 1996,
50–3.
2. Foster S, Yue CX. Herbal Emissaries: Bringing Chinese Herbs to the
West. Rochester, VT: Healing Arts Press, 1992, 27–33.
3. Shu HY. Oriental Materia Medica: A Concise Guide. Palos
Verdes, CA: Oriental Healing Arts Press, 1986, 521–3.
4. Klepser T, Nisly N. Astragalus as an adjunctive therapy in
immunocompromised patients. Alt Med Alert 1999;Nov:125–8 [review].
5. Klepser T, Nisly N. Astragalus as an adjunctive therapy in
immunocompromised patients. Alt Med Alert 1999;Nov:125–8 [review].
6. Qun L, Luo Q, Zhang ZY, et al. Effects of astragalus on IL-2/IL-2R
system in patients with maintained hemodialysis. Clin Nephrol 1999;52:333–4
[letter].
7. Tang W, Eisenbrand G. Chinese Drugs of Plant Origin. Berlin:
Springer Verlag, 1992, 1056.
8. Li SQ, Yuan RX, Gao H. Clinical observation on the treatment of
ischemic heart disease with Astragalus membranaceus. Chung Kuo Chung His I Chieh Ho Tsa
Chih 1995;15:77–80 [in Chinese].
9. Foster S. Herbs for Your Health. Loveland, CO: Interweave
Press, 1996, 6–7.
Copyright © 2002 Healthnotes, Inc. All rights reserved.
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The information presented in Healthnotes is for informational
purposes only. It is based on scientific studies (human, animal, or in vitro),
clinical experience, or traditional usage as cited in each article. The results reported may
not necessarily occur in all individuals. For many of the conditions discussed, treatment with
prescription or over-the-counter medication is also available. Consult your doctor,
practitioner, and/or pharmacist for any health problem and before using any supplements or
before making any changes in prescribed medications. Information expires December 2003.
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