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Photo copyright Steven Foster

Ephedra

Common name: Ma huang

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.

Warning: Ephedra should be taken only with medical supervision. Ephedra is not for sale in certain parts of the world.

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? Standardized extracts supplying 12–25 mg of total alkaloids (calculated as ephedrine) per capsule or tablet may be taken. This form may be useful for monitoring total daily intake of ephedrine. A scientific review of ephedra safety4 says ephedra should be limited to no more than 30 mg per dose and no more than 90 mg per day of the ephedrine alkaloids. Use should be limited to six months or less5 . The crude powdered stems of ephedra (with less than 1% ephedrine) are used at 1.5–6 grams per day, taken as a tea.6 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.

Are there any side effects or interactions? Use 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.7 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.8 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.9 Long-term (months or more) overdose of ephedra or ephedrine can potentially cause kidney stones composed of ephedrine, though this is rare.10 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.”11 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, kidney disease, diabetes, glaucoma, hyperthyroidism, anxiety or restlessness, impaired circulation to the brain, neurological disorders, benign prostatic hyperplasia with residual urine accumulation, pheochromocytoma (primary adrenal tumor), and those taking MAO-inhibiting antidepressants, digitoxin, ephedrine, or guanethidine should consult with a physician before using any type of product containing ephedra.12 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 eighteen years without medical supervision.13

Are there any drug interactions? Certain medications may interact with ephedra. Refer to the drug interactions safety check for a list of those medications.

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. Institute of Medicine. Dietary Reference Intakes: a risk assessment model for establishing upper intake levels for nutrients. Washington, DC: National Academy Press, 1998.

5. Cantox Health Sciences International. Safety assessment and determination of a tolerable upper limit for ephedra. December 19, 2000. www.crnusa.org/CRNCantoxreportindex.html.

6. Foster S. Herbs for Your Health. Loveland, CO: Interweave Press, 1996, 37–8.

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. 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.

9. 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.

10. Powell T, Hsu FF, Turk J, Hruska K. Ma-huang strikes again: Ephedrine nephrolithiasis. Am J Kidney Dis 1998;32:153–9.

11. 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.

12. 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.

13. Cantox Health Sciences International. Safety assessment and determination of a tolerable upper limit for ephedra. December 19, 2000. www.crnusa.org/CRNCantoxreportindex.html