General Description
Ephedra (also known as ma huang, desert tea, or mormon tea) is a
small, branched shrub native to desert regions of inner Mongolia
and northern China, with related species found in desert regions
throughout the world. The plant has grooved, cylindrical stems,
which range from 30 to 90 centimeters in height, and small, scale-like
leaves, which reach two to four millimeters in length. The plant
has separate male and female flowers, which grow in yellowish-green,
terminal catkins, with the female catkins eventually producing a
red, berry-like false fruit. The dried green stems are used medicinally.
Health Applications
- Cough/congestion
- Asthma/respiratory tract health
- Hayfever/allergy
- Weight loss
- Athletic performance
History and Traditional Use
Evidence from archeological excavations in Iraq suggests that
ephedra may have been used medicinally by Neanderthals in the
Middle Paleolithic Age.1 In China, ephedra
has a history of medicinal use that dates back over 5,000 years.2
In traditional Chinese medicine, ephedra was used to induce sweating,
to ventilate the lungs and relieve asthma, and to regulate water
metabolism.3
Chemical Composition
The active constituents in ephedra are a group of alkaloid compounds
that includes ephedrine, pseudoephedrine, norephedrine, and norpseudoephedrine.4
The compounds work by indirectly stimulating the central nervous
system.4,5
Contemporary Uses
Modern herbalists commonly recommend ephedra for asthma, hayfever,
the common cold, and as a weight-loss aid.6
Germany's Commission E lists ephedra as an approved herb for diseases
of the respiratory tract with mild bronchospasms (in adults and
children over age six).5 Ephedra alkaloids
have long been used to treat bronchial asthma and as nasal decongestants,
and the herb appears to be useful for these applications.2
Because ephedra acts as a strong central nervous system stimulant,
it is often promoted as a weight-loss aid and enhancer of athletic
performance; however, the efficacy of the herb for these purposes
has not been demonstrated.2
Dosage/Toxicity
The daily dosage recommendation for ephedra varies with the alkaloid
content of the plant. For adults, Commission E recommends single
doses of preparations corresponding to 15-30 mg of total alkaloid
content (calculated as ephedrine), with a maximum daily dosage
of 300 mg. For children, the dosage should correspond to 0.5 mg
of total alkaloid per kg (2.2 lb) of body weight, with a maxiumum
daily dosage of 2 mg total alkaloid per kg of body weight.5
Ephedra use has been associated with numerous side effects such
as insomnia, restlessness, irritability, headaches, nausea, vomiting,
urinary disturbances, accelerated heart rate, and, in higher dosages,
cardiac arrhythmia and drastic increase in blood pressure.5
Ephedra is not recommended for use by people suffering from anxiety,
high blood pressure, glaucoma, impaired circulation to the cerebrum,
prostate adenoma, or thyroid disorders.4,5
Because ephedra has been shown to interact with a variety of drugs,4,5
people taking prescription medications should only take the herb
under a doctor's supervision. Because of the danger of developing
dependence, long-term use of ephedra is not recommended.4
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