Ephedras Ephedra Ephedrine

Several alkaloids are present in Ephedra, with ephedrine being the most significant (Gruenwald et al. 1998). Ephedra sinica contains approxi-... 

The principal active ingredient in ephedra is ephedrine. Synthetically produced ephedrine has been approved by the FDA for use as a drug. Under those more controlled conditions, the compound has not been associated with any adverse events of the kind reported for the natural product. 

Phenylalanine-derived Ephedraceae Ephedra intermedia Ephedrine... 

OFFICIAL NAMES Ephedra, Ephedra sinica STREET NAMES Mahuang, ma huang, desert tea, Mormon tea, American ephedra, European ephedra, Pakistani ephedra, ephedrine, ephedrine alkaloids, pseudoephedrine DRUG CLASSIFICATIONS Not scheduled, dietary supplement... 

The oriental crude drug Ma Huang or Mao, prepared from certain species of the genus Ephedra, contains ephedrine, pseudoephedrine, and homologous compounds (2). Although alkaloids of the ephedrine type occur in several Ephedra species, only a few other plant sources are known (Table IV and V). 

The six optically active alkaloids ephedrine, pseudoephedrine, norephedrine, norpseudoephedrine, and the N-methylated N-methylephedrine and N-methylpseudoephedrine are described in detail in Reti s review (2). Two new alkaloids of related structure have since been identified in Ephedra species, namely, (9-benzoylpseudoephedrine (271) and the oxazolidine derivative ephe-droxane (272). The 4-quinolone derivative ephedralone, recently isolated from Ephedra alata (273), may be of similar biogenetic origin as the ephedrines. Ephedra species also contain macrocyclic alkaloids of more complex structure (275). The two major Ephedra alkaloids (—)-ephedrine and (+)-pseudoephedrine are diastereomers. (—)-Ephedrine has the erythro and (+)-pseudoephedrine has the threo configuration. 

Ephedra. Ephedras are leafless bushes that grow in deserts throughout the world. They are related to pine trees and bear tiny cones. Several species contain the drug ephedrine, a stimulant and a remedy for asthma. American ephedra, found throughout the western United States, is known as Mormon tea because early... 

A number of plant species from the genus Ephedra have been used for many years for their stimulant effects. Ephedra sinica is native to Asia and is frequently sold under its Chinese name, ma huanpf. Another species, E. nevadensis, grows in the American West and is known as Mormon tea. The main psychoactive compound in ephedra is ephedrine. Ephedrine is a potent stimulant with effects much like those reviewed in Chapter 6. It is sympathomimetic and produces behavioral effects similar to those of other stimulants (Karch, 2000). Until 2004, ephedrine products were marketed through stores or by mail order to increase energy, prevent drowsiness, suppress appetite, and in high-dose formulations, as an herbal alternative to ecstasy (see Chapter 12). These products contained a wide variety of plant products and... 

Table 2 Federal and State regulatory actions against ephedra and ephedrine-containing alkaloids ...

Many cases of serious adverse effects and even fatalities have been reported that were linked with ephedra or ephedrine administration over the last 10 years. Haller and Benowitz published a review of 140 reports of adverse events related to the use of ephedra alkaloids that were submitted to the FDA between June 1997 and March 1999. Using standardized rating system for assessing causation, 31% of the cases were considered to be definitely or probably related to the use of ephedra alkaloid-containing supplements, and another 31% were deemed to be possibly related. Among these adverse events, 47% involved in cardiovascular symptoms and 18% involved the CNS. Hypertension was the most frequent adverse effect, followed by palpitations, tachycardia, or both stroke and seizures. Ten events led to death and 13 cases produced permanent disability. 

As with other sympathomimetic agents, theoretical drug interactions with ephedra alkaloids are possible. Despite this potential, only a handful of adverse drug interactions have been reported. This is especially pertinent when considering the extensive use of both ephedra-containing supplements and ephedrine- or pseudoephedrine-containing OTC products. The most notable interaction exists between nonselective monoamine oxidase inhibitors and ephedra- or ephedrine-containing products. 

Shekelle PG, Hardy ML, Morton SC, et al. Efficacy and safety of ephedra and ephedrine for weight loss and athletic performance a meta-analysis. JAMA 2003 289 1537-1545. 

Clinically important, potentially hazardous interactions with amitriptyline, amoxapine, benzphetamine, chlorpromazine, clomipramine, desipramine, doxepin, ephedra, ephedrine, imipramine, insulin, insulin glargine, minoxidil, nortriptyline, oxprenolol, protriptyline, tricyclic antidepressants, trimipramine, zuclopenthixol, zuclopenthixol acetate, zuclopenthixol decanoate, zuclopenthixol dihydrochloride... 

Shekelle, P., Hardy, M., Morton, S., Maglione, M., Mojica, W., Suttorp, M., Rhodes, S., Jungvig, L., and Gagne, J. 2003a. Efficacy and safety of ephedra and ephedrine for weight loss and athletic performance A meta-analysis. JAMA 289, 1537-1545. 

Several amino alcohols have been isolated from Ephedra species ephedrine (3), norephedrine (1), pseudoephedrine (or t/ -ephedrine, 4), and norpseudoephedrine (2). The pseudocompounds are diastereomers of the corresponding alkaloids. 

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