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Photo copyright Steven Foster
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Botanical names: Ephedra sinica, Ephedra
intermedia, Ephedra equisetina
Parts used and where grown: Ephedra is a shrub-like plant
found in desert regions throughout the world. It is distributed from northern China to Inner
Mongolia. The dried green stems of the three Asian species (Ephedra sinica, E. intermedia,
E. equisetina) are used medicinally. The North American species of ephedra, sometimes
called Desert Tea or Mormon Tea, does not appear to contain the active ingredients of its
Asian counterparts.
Ephedra 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): The Chinese have used ephedra medicinally
for over 5,000 years. Ephedra is listed as one of the original 365 herbs from the classical
first century A.D. text on Chinese herbalism by Shen Nong.1 Ephedra’s
traditional medicinal uses include the alleviation of sweating, lung and bronchial
constriction, and water retention. Coughing, shortness of breath, the common cold, and fevers without sweat are all indications for
its use. While its active constituent, ephedrine, was
isolated in 1887, the herb did not become popular with U.S. physicians until 1924 for its
bronchodilating and decongesting properties.2
Active constituents: Ephedra’s main active medicinal
ingredients are the alkaloids ephedrine and pseudoephedrine. The stem contains 1–3%
total alkaloids, with ephedrine accounting for 30–90% of this total, depending on the
plant species.3 Both ephedrine and its synthetic counterparts stimulate the central
nervous system, dilate the bronchial tubes, elevate blood pressure, and increase heart rate. A
synthetic form of pseudoephedrine is a popular over-the-counter remedy for relief of nasal congestion. Little research has been done on the
whole plant (compared to its isolated alkaloids) for any condition.
How much is usually taken? The crude powdered stems of ephedra
(with less than 1% ephedrine) are used at 1.5–6 grams per day, taken as a
tea.4 The crude herb can also be taken in capsule or tablet form, at
500–1,000 mg of ephedra two to three times daily. Tinctures of 1–4 ml three times
per day can be taken. Alternatively, standardized extracts supplying 12–25 mg of total
alkaloids (calculated as ephedrine) per capsule or tablet
may be taken two to three times daily. This form may be preferable for monitoring total daily
intake of ephedrine.
Are there any side effects or interactions? Ephedra has a long
history of safe use at the recommended amounts. However, abuse of ephedra (and particularly
ephedrine)—especially for weight loss or as a
recreational drug—can lead to amphetamine-like side effects, including elevated blood
pressure, rapid heart beat, nervousness, irritability, headache, urination disturbances,
vomiting, muscle disturbances, insomnia, dry mouth,
heart palpitations, and even death due to heart failure.5 One study has shown that
a single application of ephedra caused mild elevation of heart rate but did not consistently
affect blood pressure in otherwise healthy adults.6 When taken at higher levels,
ephedra can cause drastic increases in blood pressure, as well as cardiac arrhythmias.
Ephedrine is considered potentially habit-forming, though it is unclear if the whole herb
ephedra is likely to have the same effect.7 Long-term (months or more) overdose of
ephedra or ephedrine can potentially cause kidney stones composed of ephedrine, though this is
rare.8 A review of 140 reports of heart and nervous-system emergencies concluded
that one-third of the adverse health reports were “definitely or probably related”
to ephedra and another one-third “possibly related.”9 All of the cases
cited were people taking ephedra together with either
caffeine and/or drugs with known cardiovascular side effects, such as theophylline and
phenylpropanolamine.
Anyone with high blood pressure, heart conditions, diabetes, glaucoma,
hyperthyroidism, anxiety or restlessness, impaired
circulation to the brain, benign prostatic hyperplasia with
residual urine accumulation, pheochromocytoma (primary adrenal tumor), and those taking
MAO-inhibiting antidepressants, digitoxin, or
guanethidine should consult with a physician before using any type of product containing
ephedra.10 Pseudoephedrine can cause drowsiness and should be used with caution if
driving or operating machinery. Ephedra-based products should be avoided during pregnancy and breast-feeding and should not be used in children
under the age of six years without medical supervision.
Are there any drug interactions? Certain medications may
interact with ephedra. Refer to the drug interactions
safety check for a list of those medications.
Special United Kingdom consideration: Ephedra may be
prescribed by a medical doctor or dispensed by an herbal practitioner at a maximum daily dose
of 1,800 mg.
References:
1. Foster S. Herbs for Your Health. Loveland, CO: Interweave
Press, 1996, 37–8.
2. Tyler, VE. The Honest Herbal, 3d ed. Binghamton, NY:
Pharmaceutical Products Press, 1993, 119–21.
3. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients
Used in Food, Drugs, and Cosmetics, 2d ed. New York: John Wiley & Sons, 1996,
227–9.
4. Foster S. Herbs for Your Health. Loveland, CO: Interweave
Press, 1996, 37–8.
5. Blumenthal M, Busse WR, Goldberg A, et al. (eds). The Complete
Commission E Monographs: Therapeutic Guide to Herbal Medicines. Boston, MA: Integrative
Medicine Communications, 1998, 125–6.
6. White LM, Gardner SF, Gurley BJ, et al. Pharmacokinetics and
cardiovascular effects of ma-huang (Ephedra sinica) in normotensive adults. J
Clin Pharmacol 1997;37:116–21.
7. Blumenthal M, Busse WR, Goldberg A, et al. (eds). The Complete
Commission E Monographs: Therapeutic Guide to Herbal Medicines. Boston, MA: Integrative
Medicine Communications, 1998, 125–6.
8. Powell T, Hsu FF, Turk J, Hruska K. Ma-huang strikes again: Ephedrine
nephrolithiasis. Am J Kidney Dis 1998;32:153–9.
9. Haller CA, Benowitz NL. Adverse cardiovascular and central nervous
system events associated with dietary supplements containing ephedra alkaloids. New Engl J
Med 2000;343:1833–8.
10. Blumenthal M, Busse WR, Goldberg A, et al. (eds). The Complete
Commission E Monographs: Therapeutic Guide to Herbal Medicines. Boston, MA: Integrative
Medicine Communications, 1998, 125–6.
Copyright © 2002 Healthnotes, Inc. All rights reserved.
www.healthnotes.com
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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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