[Cuzimdmom]

Here is some great info I just received detailing Ephederine Alkaloids, found in Herbalean ER. Some have questioned me on this and now that I know, I wanted to share it with you.

About 40 different species of ephedra grow in many regions of the world, including North America. American species do not contain measurable alkaloids, but Asian species contain varying amounts of several pharmacologically active ephedrine alkaloids, primarily ephedrine and pseudoephedrine. These usually comprise between 0.5 and 2.5 percent by weight of dried ephedra tops, the part of the herb used medicinally. Considerable variations in alkaloid content occur among species and with time of harvest. The plant's alkaloid content is usually highest in the fall. Extracts of this plant have become important to the drug industry because of the nervous system effects of the alkaloids they contain. They have also found their way into dietary supplements.

Pharmacological Effects
Although ephedra extracts should not be confused with the alkaloids they contain, a study of the latter is the best way to understand the extracts' general pharmacological effects. The alkaloid ephedrine, ranging from 30 to 90 percent of the alkaloid content of ephedra, is primarily responsible for ephedra's bronchodilatory action. Ephedrine quickly relieves the spasm of bronchial muscle that causes an asthma attack. Ephedrine also raises blood pressure and increases heart rate. These actions stimulate the sympathetic portion of the autonomic nervous system.

Biologically speaking, our autonomic nervous system functions either in a parasympathetic, or housekeeping mode of relaxing and digesting, or a sympathetic one of preparing to fight the perceived saber-toothed tiger. The body naturally responds to sympathetic hormones secreted by the adrenal glands, producing adrenaline that raises blood pressure, pumps more blood, and shunts it away from the internal organs to skeletal muscles in arms and legs. Pupils dilate and take in more light for better vision, and bronchioles open for easier breathing. This concerted response makes one ready to do battle or flee, the so-called fight-or-flight response.
The ephedrine alkaloids have a chemical structure close to that of the body's natural adrenaline and act in a similar fashion. Like adrenaline, they belong to the class of adrenergic or adrenalinelike amines. When John Travolta plunged a syringe into Uma Thurman's heart in Pulp Fiction's drug-overdose scene, he was directly administering adrenaline to treat cardiac failure. Unlike adrenaline, ephedrine is active only orally, but its effects last about 10 times longer, making it an extremely useful tool in Western medicine. Its ability to increase blood pressure, cardiac output and heart rate has been used to control dangerous drops in blood pressure during spinal and epidural anesthesia. Ephedrine's pharmacological action is comparable to amphetamine but at about one-fifth the potency.

Weighing in on Ephedrine
The stimulatory effects of ephedrine alkaloids make them popular ingredients in weight-loss and performance products. One theory describing the weight-loss action of products containing ephedrine alkaloids is that they increase the rate of thermogenesis, or heat production, in the body. Many dietary supplements geared toward weight loss combine a source of ephedrine with other stimulants such as caffeine.


Steven J. Dentali, Ph.D., is a pharmacognosist who wrote safety reviews on ephedra and kava for the Herb Research Foundation and served on the FDA ephedrine alkaloid working group.
References
1. Chen K.K. A pharmacognostic and chemical study of ma huang (Ephedra vulgaris var. helvetica). J Am Pharm Assoc 1925;14:189-94.

2. Chen KK, Schmidt CF. Action of ephedrine, the active principle of the Chinese drug ma-huang. J Pharmacol Exp Therap 1924;24:339-57.

3. Feng CT, Read BE. Comparison of Ephedra equisetina and Ephedra sinica and their seasonal content of ephedrine. Chinese J Physiol 1928;2:87-96.

4. [Anonymous]. The ephedras. Lawrence Rev Nat Products 1989 Jun.

5. Bensky D, Gamble A. Chinese herbal medicine: materia medica. Seattle (WA): Eastland Press; 1986. p 32-4.

6. Martin WR, et al. Physiologic, subjective, and behavorial effects of amphetamine, methamphetamine, ephedrine, phenmetrazine, and methylphenidate in man. Clin Pharmacol Ther 1971;12:245-58.

7. Storms WW, et al. SCH 434: a new antihistamine/decongestant for seasonal allergic rhinitis. J Allergy Clin Immun 1989;83:1083-90.

8. Dollery C, editor. Phenylpropanolamine (hydrochloride). In: Therapeutic Drugs. (Scotland): Churchill Livingstone; 1991. p 91-3.

9. Bruno A, et al. Stroke associated with ephedrine use. Neurology 1993;43:1313-6.

10. Whitehouse AM, Duncan JM. Ephedrine psychosis rediscovered. Br J Psychiatry 1987;150:158-261.

11. Hu S, Wang G. Textual studies on shangzhou zhiqiao fructus Aurantii. Chung Kuo Chung Yao Tsa Chih 1996;21:137-8, 189.

12. Huang YT, et al. Fructus aurantii reduced portal pressure in portal hypertensive rats. Life Sci 1995;57:2011-20.