Ephedra sinica - Ma Huang

Description

This fragrant perennial shrub has glabrous stems, smooth and purplish, with light linear striations, growing about 1.5 - 3 m high. The inferior leaves are tripinnate, superior leaves are often simply pinnate; leaflets are oval, dentate-incised, the teeth obtuse; petiole is 3-11 cm long, sheathed, bracts are rudimentary, not prominent. The florets are in umbels (10-14), with irregular rays. The flowers are white, five-petalled, blooming June-July. The fruit appears July-Aug. Ma Huang is grown in China, Korea and Japan.

Part Used

green herbaceous stems.

Constituents

Ma Huang contains between 0.44 - 2.56% alkaloid content varying between species and time of the year of picking; the highest alkaloid content being in September. The alkaloid content is mostly l-ephedrine (ca.50 - 85%) with the next most important one being d-pseudoephedrine. There are also small amounts of other related alkaloids present. The chemical pathway seems to be a biosynthesis of phenylalanine and methionine into ephedrine. There are also present: glycans (ephedrans A-E), volatile oils (includes limonene, caryophyllene, phellandrene and others); small amounts of saponins, catechin, and tannins.(1-7)

Mode of Action

Ephedrine is classed as an adrenergic bronchiodilator. It excites the sympathetic nervous system, depressing smooth muscle and cardiac muscle action, producing similar effects to those of epinephrine. Its major difference from epinephrine is that it is not changed in the GI tract nor upon absorption. It also has a more prolonged effect. Ephedrine is known to raise blood pressure, diminish hyperemia and dilate the pupils. There is a definite though mild sudorific effect upon taking this herb. It will reduce the temperature. Pseudoephedrine exerts a dilating effect upon the renal blood vessels. The essential oil has been shown to be antiviral.(8) Other uses include malarial fevers, rhinitis, asthma, hay fever, emphysema, epilepsy, nocturnal enuresis, myasthenia gravis. D-pseudoephedrine increases urine output, reduces spasms in bronchial smooth muscles and stimulates striated muscle.(9-25)

The alkaloids have been shown to have anti-inflammatory activity on experimental edema. The glycans produced significant hypoglycemic effect. Ma Huang is often used as an anti-air-bound-allergy treatment.(26)

There has been much controversy over the use of Ma Huang, as it has also been employed in weight loss, sexual stimulant and euphoria type products. Abuse of Ma Huang can cause insomnia, motor disturbance, high blood pressure, glaucoma, impaired cerebral circulation, and urinary disturbances. There have been several reported cases of cardiac infarction and even deaths related to overuse. While highly controversial, the results of these cases is not conclusive. For this reason the US FDA want to limit Ma Huang use to no more that 8 mg of ephedrine per dosage and no more than 24 mg daily. As of this writing this has not been put into effect.(27)

Therapeutic Action

Expectorant, nervine, sedative.

Energetics

Traditional Chinese

The herb is acrid, slightly bitter and warm, entering the Lung and Bladder meridians. Ma Huang releases the exterior and disperses cold, facilitates Lung Qi circulation and controls wheezing.(28,29) The root (Ma Huang Gen) is sweet with a neutral character and enters the Lung meridian. It stops qi deficiency caused by Blood deficiency.(30,31)

Other

Tierra lists ephedra (herb) as pungent, bitter and warm entering both Lung and Bladder meridians.(32)

Folklore

Used in Chinese medicine since the Divine Husbandman`s Classic of Materia Medica (1596 A.D.). While Ephedra sinica did not appear in Native Amerindian ethnobotanies, a number of Ephedra species (generally called Mormon tea or Indian tea) were used extensively by the tribes of the Southwest.(33)

Dosage

Powder - ½ - 10 gms
Extract - 10 - 30 mg

Toxicity and Contraindications

Ma Huang is contraindicated in cases of heart problems and high blood pressure. The toxic dose is 30 - 45 grains per day of powder and 90 mg of the extract. The antidote to ephedrine toxicity is licorice (15 gms) or 6 gms of Ma Huang root or nodes.

Official Recognition and Medical References

Germany - Commission E., p. 125
PDR for Herbal Medicine, p. 827

References

1. The British Pharmaceutical Codex 1934, Pharmaceutical Press, London, 1934, p. 409.
2. The Merck Index, 5th Ed., Merck & Co. Inc., Rahway, N.J., 1940, p. 213.
3. Trease, G.E., and Evans, W.C., Pharmacognosy (11th Ed.), Bailliere Tindall, London, 1978, p. 566.
4. Remington`s Pharmaceutical Sciences, Philadelphia College of Pharmacy and Science, Mack Publishing Co., Easton, Penn., 1980, p. 822.
5. Chen, K.K., and Schmidt, C.F., Ephedrine and Related Substances, Williams and Wilkins Co., Baltimore, Md., 1930, p. 7-15.
6. Duke, J.A., Handbook of Medicinal Herbs, CRC Press Inc., Boca Raton, FL, 1985, p. 176
7. Leung, A.Y. and S. Foster, Encyclopedia of Common Natural Ingredients: Used in Food, Drugs, and Cosmetics, John Wiley & Sons, Inc., New York, 1996, p. 227
8. Hsu, H.Y., Chen, Y.P., et al., Oriental Materia Medica: a concise guide, Oriental Healing Arts Institute, Long Beach, CA, 1986, p. 600.
9. Yeung, H.C., Handbook of Chinese herbs and Formulas, Vol.1, Institute of Chinese Medicine, Los Angeles, 1985. p.376.
10. British Pharmaceutical Codex 1934, Ibid.
11. Tyler, V.E., Pharmacognosy, 6th Ed., Lea & Febiger, Phila., PA, 1976, p. 290
12. Morton, J.F., Major Medicinal Plants: Botany, Culture and Uses, Charles C. Thomas, Springfield, Ill., p. 34.
13. The Merck Index (5th Ed.), Ibid.
14. Wood, H.C., and Osol, A., Dispensatory of the United States of America, 23rd ed., J.B. Lippincott, Montreal, PQ, 1943, p. 405.
15. Trease, G.E., and Evans, W.C., Ibid.
16. Ross, M.S.F., and Brain, K.R., An Introduction to Phytopharmacy, Pitman Medical, Tunbridge Wells, U.K., 1977, p. 179.
17. Youngken, H.W., Textbook of Pharmacognosy, Blakiston, Toronto, Can., 1950, p. 112.
18. Herbal Pharmacology in the People`s Republic of chins, Trip Report of the American Herbal Pharmacology Delegation, National Academy of Sciences, Washington, D.C., 1975, p. 139.
19. Wallis, T.E., Textbook of Pharmacognosy, J. & H. Churchill, London, 1967, p. 301.
20. Allport, N.L., Chemistry and Pharmacy of Vegetable Drugs, George Newnes Ltd., London, 1943, p.76.
21. Chen, K.K., and Schmidt, C.F., Ibid. p. 15-82.
22. Pang, T.Y., Chinese Herbal, Tai Chi School, Honolulu, 1982, p. 166.
23. Wren, R.C., Potter`s New Cyclopedia of Botanical Drugs and Preparations, Health Science Press, Rustington, Sussex, U.K., 1975, p. 113.
24. Remingtons`s Pharmaceutical Sciences, Ibid.
25. Bensky, D. and Gamble, A., Chinese Herbal Medicine: Materia Medica, Eastland Press, Seattle, WA, 1986, p. 32-34.
26. Leung Foster abid
27. Reunter report; FDA Seeks Limits on Ephedrine Products; Westport Newsroom, June 03 1999
28. Hsu, H.Y., Chen, Y.P., et al., Ibid. p. 52-53.
29. Bensky, D. and Gamble, A., Ibid., p. 32-34.
30. Bensky, D. and Gamble, A., Ibid., p. 562-563.
31. Hsu, H.Y., Chen, Y.P., et al., Ibid., p. 606-607.
32. Tierra, M., Planetary Herbology, Lotus Press, Santa Fe, NM, 1988, p. 148.
33. Moerman, D.E., Medicinal Plants of Native America, University of Michigan Museum of Anthropology, Technical Reports, Number 19, Ann Arbor, Michigan, 1986, Vol.1, p. 160.