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© Steven Foster |
Some athletes say that ephedra
Instead of using pharmaceutical asthma medications, some athletes who have asthma prefer to use ephedra as a natural alternative. As a stimulant, ephedra can be taxing on the body and endanger health. Discuss the pros and cons of using ephedra for asthma with your doctor.
Warning: Ephedra should only be taken with medical supervision. Ephedra is not for sale in certain parts of the world.
Ephedra (ma huang) has been used to improve training performance, but the herb and its alkaloids, ephedrine and pseudoephedrine, are banned by the International Olympic Committee.1 When taken with caffeine, ephedrine has been shown to improve the performance of high-intensity aerobic exercise lasting up to about 30 minutes. The effective amounts were 4 to 5 mg of caffeine per 2.2 pounds of body weight and 0.8 to 1.0 mg of ephedrine per 2.2 pounds of body weight.2 3 4 At the higher intakes of ephedrine plus caffeine, many people experienced nausea and vomiting. In other double-blind trials, ephedrine alone at 0.8 to 1.0 mg per 2.2 pounds of body weight has been shown to increase power output at the beginning of an anaerobic cycling exercise and to improve performance equally well compared with an ephedrine-caffeine combination, either in a 10 kilometer run lasting over 40 minutes or during weight-training sessions.5 6 7 In the latter study, blood pressure was significantly increased by ephedrine. No research has investigated whether ephedra herb can produce any of these effects.
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.8 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.9 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.10 Long-term (months or more) overdose of ephedra or ephedrine can potentially cause kidney stones composed of ephedrine, though this is rare.11 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.”12 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.13 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.14
Are there any drug
interactions?
Certain medicines may interact with ephedra. Refer to
drug interactions for a list of those medicines.
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.
*Athletes and fitness advocates may claim benefits for ephedra based on their personal or professional experience. These are individual opinions and testimonials that may or may not be supported by controlled clinical studies or published scientific articles on ephedra. For more complete and detailed information, including references and safety information, see Ephedra as an herbal remedy.
1. Barron RL, Vanscoy GJ. Natural products and the athlete: facts and folklore. Ann Pharmacother 1993;27:607–15 [review].
2. Bell DG, Jacobs I, Zamecnik J. Effects of caffeine, ephedrine and their combination on time to exhaustion during high-intensity exercise. Eur J Appl Physiol Occup Physiol 1998;77:427–33.
3. Bell DG, Jacobs I, McLellan TM, Zamecnik J. Reducing the dose of combined caffeine and ephedrine preserves the ergogenic effect. Aviat Space Environ Med 2000;71:415–9.
4. Bell DG, Jacobs I. Combined caffeine and ephedrine ingestion improves run times of Canadian Forces Warrior Test. Aviat Space Environ Med 1999;70:325–9.
5. Bell DG, Jacobs I, Ellerington K. Effect of caffeine and ephedrine ingestion on anaerobic exercise performance. Med Sci Sports Exerc 2001;33:1399–403.
6. Bell DG, McLellan TM, Sabiston CM. Effect of ingesting caffeine and ephedrine on 10-km run performance. Med Sci Sports Exerc 2002;34:344–9.
7. Jacobs I, Pasternak H, Bell DG. Effects of ephedrine, caffeine, and their combination on muscular endurance. Med Sci Sports Exerc 2003;35:987–94.
8. 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.
9. 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.
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.
11. Powell T, Hsu FF, Turk J, Hruska K. Ma-huang strikes again: Ephedrine nephrolithiasis. Am J Kidney Dis 1998;32:153–9.
12. 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.
13. 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.
14. Cantox Health Sciences International. Safety assessment and determination of a tolerable upper limit for ephedra. December 19, 2000. www.crnusa.org/CRNCantoxreportindex.html
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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 July 2004.