Common Names

  • Mahuang
  • herbal ecstasy

For Patients & Caregivers

How It Works

Ephedra is a stimulant that has caused heart attack and stroke resulting in several deaths.

Ephedra contains ephedrine and pseudoephedrine, which are known to stimulate the central nervous system (brain and spinal cord). They activate the “fight or flight” response, resulting in constriction of blood vessels, relaxation and dilation of air passages, appetite suppression, and general stimulant effects. While these effects explain the use of ephedra as a decongestant, weight loss supplement, and anti-asthma agent, in high doses ephedra can raise blood pressure and cause adverse reactions such as stroke and heart attack. Even a single dose of an ephedra containing supplement can cause dangerous increases in blood pressure and effects on heart function.

Laboratory studies indicate that ephedra also can kill bacteria on contact, reduce inflammation, and cause contraction of the muscles of the uterus. These effects have not been studied in humans.

Purported Uses
  • To treat asthma
    Ephedra may stimulate bronchial dilation. Alkaloids from ephedra have been used in over-the-counter medication as asthma remedies and nasal decongestants.
  • To treat coughs and bronchitis
    Ephedra may stimulate bronchial dilation, but human data are lacking. The risk of dangerous side effects of ephedra may outweigh any benefits.
  • To treat the common cold
    No scientific evidence supports this use.
  • To treat infections
    Laboratory studies show that ephedra has antibacterial properties.
  • To promote urination
    There are no data to back this claim.
  • For strength and stamina
    Ephedra stimulates the central nervous system, but humand data are lacking. The risk of dangerous side effects of ephedra may outweigh any benefits.
  • To lose weight
    Even though a few clinical trials suggest that people taking ephedra lose weight, ephedra is not safe to use, even at normal doses.
Patient Warnings
  • The FDA banned the sales of ephedra-containing dietary supplements as they pose significant health risks.
Do Not Take If
  • You have any of the following conditions: Anxiety, high blood pressure, heart disease, glaucoma, prostate enlargement, or hyperthyroidism.
  • You are pregnant. (Ephedra can stimulate contraction of the uterus).
  • You are taking aspirin (Ephedra may increase the risk of brain hemorrhage (stroke).
  • You are taking benzodiazepines or other sedatives (Ephedra may lessen their effects).
  • You are taking beta-adrenergic agonists (Ephedra may have additive effects, possibly leading to toxicity).
  • You are taking CNS stimulants (Ephedra may increase the stimulatory effects).
  • You are taking monoamine-oxidase inhibitors (MAO-Is) (Use of ephedra at the same time can cause hypertensive crisis, or dangerously high blood pressure).
  • You are taking theophylline (Ephedra may decrease its effects).
  • You are taking digoxin (Use of ephedra at the same time can cause cardiac arrhythmia).
Side Effects
  • Headache
  • Hypertension
  • Gastric mucosal injury
  • Palpitations
  • Heart attack
  • Stroke
  • Seizures
  • Insomnia
  • Psychosis
  • Death
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For Healthcare Professionals

Brand Name
Herbal Ectasy, Herbal fen-phen
Scientific Name
Ephedra sinica, Ephedra equisetina
Clinical Summary

Derived from the dried rhizome and root of the plant, ephedra has been used as a medicinal herb for thousands of years in India and China. It is commonly consumed in low doses and in combination with other herbs to promote urination, to treat asthma, bronchitis and coughs. Ephedrine and pseudoephedrine, the major constituents, are non-selective sympathomimetic agents with both alpha and beta activities and have direct and indirect CNS stimulation effects, which account for the medicinal properties of the herb. Ephedra also has antibacterial and anti-inflammatory properties (1) (2) (3). It has been widely promoted as a natural stimulant and as an appetite suppressant.

Misuse and overdose of ephedra have resulted in heart attack, stroke, seizure, psychosis and death (8). Herb-drug interactions are major concerns (1) (4) (11) (14). A single dose of a weight loss supplement containing ephedra and caffeine increased QTc interval and systolic blood pressure significantly (15). The FDA has banned the sales of dietary supplements that contain ephedra because of their significant risk to human health (12) (13).

Purported Uses
  • Asthma
  • Bronchitis
  • Common cold
  • Cough
  • Infections
  • Promote urination
  • Strength and stamina
  • Weight loss
Mechanism of Action

The major alkaloids in ephedra, ephedrine and pseudoephedrine, are CNS stimulants. They are non-selective sympathomimetic agents with both alpha and beta activities. These alkaloids can be used as decongestants because they constrict peripheral blood vessels, but in high doses, they also raise blood pressure (1) (2) (3). The CNS stimulation property contributes to ephedra’s appetite suppressant effects and its reputation as a weight loss agent (7). This effect, however, may lead to other cardiovascular adverse reactions such as stroke and heart attack (8). Ephedra’s antiasthmatic effect arises from its ability to relax bronchial smooth muscle. Studies indicate that ephedra also has antibacterial, anti-inflammatory and uterine stimulatory activities (9).


The FDA banned the sales of ephedra-containing dietary supplements and consumers are urged not to use these products (12) (13) as they pose significant health risks (6).


Anxiety, hypertension, heart disease, glaucoma, prostate enlargement, hyperthyroidism.
The safety of ephedra for use during pregnancy has not been established. Since ephedra can stimulate uterine contraction, women who are pregnant should not consume this product.
 (8) (9)

Adverse Reactions

Reported: Hypertension, palpitations, heart attack, stroke, seizures, insomnia, cardiomyopathy, psychosis and death (6) (10) (14), coronary artery aneurysm and thrombosis (16), and gastric mucosal injury (17).

Herb-Drug Interactions

CNS stimulants: May increase stimulatory effects.
Theophylline: May decrease its effectiveness (18).
Digoxin: Concomitant use can cause arrhythmia (1) (11).
Monoamine-oxidase inhibitors (MAO-I): Concomitant use can cause hypertensive crisis (4).

  1. Barnes J, et al. Herbal Medicines. Second Ed. London: Pharmaceutical Press; 2002.

  2. Bensky D, Gamble A. Chinese Herbal Medicine: Materia Medica. Revised Ed. Seattle: Eastland Press; 1993.

  3. Foster S, et al. Tyler’s Honest Herbal: A Sensible Guide to the Use of Herbs and Related Remedies. New York: Haworth Herbal Press; 1999.

  4. Gruenwald J, et al. PDR for Herbal medicines, 2nd ed. Montvale (NJ): Medical Economics Company; 1998.

  5. Huang KC. The Pharmacology of Chinese Herbs, 2nd ed. New York: CRC Press; 1999.

  6. News Release. FDA Acts to Seize Ephedra-Containing Dietary Supplements. December 6, 2005. Accessed March 7, 2013.

  7. Boozer C, et al. An herbal supplement containing Ma Huang-Guarana for weight loss: a randomized, double-blind trial. Int J Obes Relat Metab Disord 2001;25:316-24.

  8. Jellin J, editor. Natural Medicines Comprehensive Database. Therapeutic Research Faculty; 2002.

  9. Naik SD, Freudenberger RS. Ephedra-associated cardiomyopathy. Ann Pharmacother. 2004 Mar;38(3):400-3. Epub 2004 Jan 23.

  10. McBride BF, Karapanos AK, Krudysz A, Kluger J, Coleman CI, White CM. Electrocardiographic and hemodynamic effects of a multicomponent dietary supplement containing ephedra and caffeine: a randomized controlled trial. JAMA. 2004 Jan 14;291(2):216-21.

  11. Flanagan CM, Kaesberg JL, Mitchell ES, Ferguson MA, Haigney MC. Coronary artery aneurysm and thrombosis following chronic ephedra use. Int J Cardiol. 2010 Feb 18;139(1):e11-3.

  12. Lillegard JB, Porterfield Jr JR. Ephedra-Induced Gastric Mucosal Injury. Case Rep Gastroenterol. 2010 Feb 27;4(1):79-83.

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