Ephedra
James Meschino DC, MS, ROHP
General Features
Various Ephedra species of plants are found throughout the world and grow in desert or arid regions. Ephedra sinica, also known as Ma Huang, is probably the best-known Ephedra species, but there are many others. They are erect, branching shrubs whose stems and branches contain alkaloids, of which 40-90 percent is the stimulant known as ephedrine and the remaining alkaloids being primarily pseudoephedrine and norpseudoephedrine.1,2,3
Western medicine’s interest in Ephedra began in 1923, with the discovery that ephedrine possessed a number of pharmacological effects. Ephedrine was synthesized for pharmaceutical purposes in 1927 and since then both ephedrine and pseudoephedrine have been used extensively in over-the-counter cold and allergy medications.4 In 1973, more than 20 million prescriptions contained either ephedrine or pseudoephedrine.1
Principle Active Constituents
- Ephedrine
Ephedrine has similar pharmacological action as epinephrine, but is less potent. Ephedrine is also absorbed more slowly than epinephrine, but is longer acting with more sustained effects on the brain and central nervous system, but again is much less potent.4 Both ephedrine and pseudoephedrine cross the blood brain barrier resulting in stimulation of the nervous system.11
The physiological effects of ephedrine are similar to those of epinephrine and include:
- Increases blood pressure
- Increases cardiac output
- Increases heart rate
- Increases blood flow to the heart, brain, and skeletal muscle
- Decreases blood flow to the intestinal tract and kidneys
- Relaxation of bronchial muscles and uterine muscles 4
- Pseudoephedrine
Pseudoeohedrine also relaxes bronchial muscles like Ephedra, but exerts weaker effects on the heart and central nervous system. Therefore, it is often recommended in the treatment of chronic asthma instead of ephedrine.4
Clinical Application and Mechanism of Action
Weight Loss Aid
Ephedra has been shown to increase the metabolic rate and encourage the release of fatty acids from adipose tissue to the bloodstream, where they may be taken up and used as a metabolic fuel by skeletal muscle and other tissues. Ephedra acts as a sympathetic nervous system stimulant, enhancing the release of adrenaline and providing a direct thermogenic effect. 5,6
The thermogenic effect can be enhanced by methylxanthines (i.e., caffeine) and salicylates. As such, combinations of these ingredients have been used in studies with athletes and have been shown to produce ergogenic performance-enhancing effects. 7,8,9
For weight loss patients, most of the studies have used a combination of 20 mg of ephedrine and 200 mg of caffeine, three times daily. Although significant weight loss results have been achieved using this approach (i.e., 36 lbs of weight loss in 24 weeks compared to 29 lbs in the placebo group), health practitioners and consumers should be aware of the dangerous side effects that can result (see Adverse Side Effects and Toxicity) from the use of ephedrine or Ephedra-containing supplements.7
Dosage Range and Standardized Grade
Weight Loss Aid
As a weight loss aid, a common dosage is 12.5 – 25.0 mg of ephedrine, taken twice or three times per day. Most Ephedra species (i.e., Ephedra sinica or Ma Huang) are 1 – 3 percent alkaloid content, but a 10 percent standardized extract is now available. Therefore, the dosage of a 10 percent alkaloid content (Ma Huang) extract would be 125 to 250 mg, three times daily.1
Adverse Side Effects, Toxicity and Contraindications
As reported by the FDA (U.S.) Special Nutritionals Adverse Event Monitoring System, 17 percent of all adverse reactions related to dietary supplements were a result of Ephedra-containing products in 1998 (more than 800 reports).
The list of adverse side effects include:
- Nervousness
- Insomnia
- Irritability
- Psychosis
- Headache
- Dizziness
- Seizures
- Stroke
- Premature ventricular contractions
- Increased blood pressure
- Myocardial infarction (heart attack)
- Sudden death 10,12,13
The Food and Drug Administration advisory review panel on non-prescription drugs recommended that ephedrine not be taken by patients with heart disease, high blood pressure, thyroid disease, diabetes, or difficulty in urination due to enlarged prostate or by patients taking antihypertensive or antidepressant drugs.1 Other contra-indications include anxiety, glaucoma, pheochromocytoma.14
Drug-Nutrient Interactions
Ephedra-containing products should not be used concurrently by patients taking the following medications:
- Caffeine containing drugs
- Cardec DM
- Epinephrine containing drugs
- Nadolol
- Pheneizine
- Phenylpropanolamine 15
- Monoamine oxidase inhibitors (MAO-inhibitors)
- Antidepressants
- Digoxin – digitalis
- Antihypertensive drugs
- Guanethidine 16
- Any Oral or Inhaled Anti-asthmatic medication 17,18
Pregnancy and Lactation During pregnancy and lactation, the only supplements that are considered safe include standard prenatal vitamin and mineral supplements. All other supplements or dose alterations may pose a threat to the developing fetus and there is generally insufficient evidence at this time to determine an absolute level of safety for most dietary supplements other than a prenatal supplement. Any supplementation practices beyond a prenatal supplement should involve the cooperation of the attending physician (e.g., magnesium and the treatment of preeclampsia.) References: Pregnancy and Lactation 1. Encyclopedia of Nutritional Supplements. Murray M. Prima Publishing 1998.2. Reavley NM. The New Encyclopedia of Vitamins, Minerals, Supplements, and Herbs. Evans and Company Inc. 1998. 3. The Healing Power of Herbs (2nd edition). Murray M. Prima Publishing 1995. 4. Boon H and Smith M. Health Care Professional Training Program in Complementary Medicine. Institute of Applied Complementary Medicine Inc. 1997. |
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- Duke JA. Handbook of Medicinal Herbs, Boca Raton, FL; CRC Press, 1985
- Gilman AG, Goodman AS, and Gilman A. The Pharmacologic Basis of Therapeutics, New York: Macmillan, 1980
- Lee T, et.al. Adrenomimetic Drugs in Craig C, Stitzel R, eds., Modern Pharmacology (4th edition), New York;Little, Brown and Company 1994:907
- Astrup A, et.al.. The Effect of Chronic Ephedrine Treatment on Substrate Utilization, the Sympatho-Adrenal Activity, and Expenditure During Glucose-induced Thermogenesis in Man, Metabolism 1986;35:260-265
- Astrup A, et.al.. Pharmacology of Thermogenic Drugs, AM J Clin Nutr 1992;55(1):246S-248S.
- Astrup A, et.al. The Effect and Safety of an Ephedrine / Caffeine Compound Compared with Ephedrine, Caffeine, and Placebo in Obese Subjects on an Energy Restricted Diet, Int J Obesity 1992;16:269-277
- Dulloo AG, et.al. The Thermogenic Properties of Ephedrine / Methyxanthine Mixtures; Human Studies, Int J Obesity 1986;10:467-481
- Colgan M. Optimum Sports Nutrition, Advanced Research Press 1993, 454-455
- McNeill JR, Interactions Between Herbal and Conventional medicines, Can J Cont Medical Educ 1999;11(12):97-110
- Nightingale SL. From the Food and Drug Administration, JAMA 1996;275(20):p1534
- Kikutani T. Contrary Views on Chinese Herbal Drugs and Side Effects, Int J Oriental Med 1990;15(4):184-188
- Blumenthal M, et.al. The Complete German Commission E Monographs: Therapeutic Guide to Herbal medicine, Austin, Texas;American Botanical Council 1998:p685
- Healthnotes Online, Healthnotes, Inc. 2000
- Blumenthol M, et.al.(eds.) The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines, Boston, MA;Integrative Medicine Communication 1998:125-126
- Faurshou M, et al. {The bronchodilating effect of ephedrine tablets in bronchial asthma}. Ugeskr Laeger 1993;155(46):3784-5
- Laitinen LA, et al. A comparison of the bronchodilator action of pseudoephedrine and ephedrine in patients with reversible airway obstruction. Eur J Clin Pharmacol 1982;23(2):107-9