Part Used: green herbaceous stems.
Mode of Action: This herb has been used in Chinese medicine since the Divine Husbandman’s Classic of Materia Medica (500 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. 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. 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.
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.
There has been much controversy over the use of Ma Huang, as it has also been employed in weight loss, sexual stimulants, 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 are not conclusive.
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. The root (Ma Huang Gen) is sweet with a neutral character and enters the Lung meridian. It stops qi deficiency caused by Blood deficiency.