Ma Huang is a strongly stimulant acrid-tasting herb that is commonly used in Chinese herbalism, where it is considered to be one of the 50 fundamental herbs[218, 254].
Most members of this genus contain various medicinally active alkaloids (but notably ephedrine) and they are widely used in preparations for the treatment of asthma and catarrh. Ephedrine has a similar effect to adrenaline in the body. It acts promptly to reduce swellings of the mucous membranes and has antispasmodic properties, thus making it valuable in the treatment of asthma. The whole plant can be used at much lower concentrations than the isolated constituents – unlike using the isolated ephedrine, using the whole plant rarely gives rise to side-effects.
The stems are a pungent, bitter, warm herb that dilates the bronchial vessels whilst stimulating the heart and central nervous system. The stems are also antidote, diaphoretic, diuretic, pectoral, vasoconstrictor and vasodilator[165, 176, 238]. They are used internally in the treatment of asthma, hay fever and allergic complaints. The plant also has antiviral effects, particularly against influenza. Ephedra is often combined with a number of other herbs and used in treating a wide range of complaints238]. This herb should be used with great caution, preferably under the supervision of a qualified practitioner. It should not be prescribed to patients who are taking monoamine oxidase inhibitors, or suffering from high blood pressure, hyperthyroidism or glaucoma. Ephedrine is seen as a performance-boosting herb and, as such, is a forbidden substance in many sporting events such as athletics[K].
The stems can be harvested at any time of the year and are dried for later use.
The root is antihydrotic, it lowers blood pressure and dilates the peripheral blood vessels. It is used in the treatment of night sweating and spontaneous sweating. The root is believed to have the opposite action to the stem, but is only prescribed in cases of profuse sweating.