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Ephedra (Chinese: ma huang, 麻黃; pinyin: má huáng, literally "hemp yellowed") is a medicinal preparation from the plant ''Ephedra sinica''. Several additional species belonging to the genus ''ephedra'' have traditionally been used for a variety of medicinal purposes, and are a possible candidate for the Soma plant of Indo-Iranian religion.〔(Botany of Haoma ), from Encyclopedia Iranica. Accessed March 15, 2007.〕 It has been used in traditional Chinese medicine for more than 2,000 years. Native Americans and Mormon pioneers drank a tea brewed from other ''ephedra'' species, called "Mormon tea" and "Indian tea". In recent years, ephedra alkaloid containing dietary supplements have been found to be unsafe, with reports of serious side effects and ephedra-related deaths.〔(【引用サイトリンク】 date = 2004-10-01 )〕〔(【引用サイトリンク】 url = http://www.fda.gov/oc/initiatives/ephedra/february2004/ )〕 In response to accumulating evidence of adverse effects and deaths related to ephedra, the U.S. Food and Drug Administration (FDA) banned the sale of supplements containing ephedrine alkaloids in 2004.〔(【引用サイトリンク】 FDA Final Rule Banning Dietary Supplements With Ephedrine Alkaloids Becomes Effective )〕 The ban was challenged in court by ephedra manufacturers, but ultimately upheld in 2006 by the U.S. Court of Appeals for the Tenth Circuit.〔(【引用サイトリンク】 FDA Statement on Tenth Circuit's Ruling to Uphold FDA Decision Banning Dietary Supplements Containing Ephedrine Alkaloids )〕 Note: Ephedra extract has not been banned by the FDA and is still sold legally today. ==Biochemistry and effects== A wide variety of alkaloid and non-alkaloid compounds have been identified in various species of ''ephedra''. Of the six ephedrine-type ingredients found in ''ephedra'' (at concentrations of 0.02-3.4%), the most common are ephedrine and pseudoephedrine. The stimulant and thermogenic effects of ''Ephedra sinica'' and other ephedra species are due to the presence of the alkaloids ephedrine and pseudoephedrine.〔 These compounds stimulate the brain, increase heart rate, constrict blood vessels (increasing blood pressure), and expand bronchial tubes (making breathing easier). Their thermogenic properties cause an increase in metabolism, as evidenced by an increase in body heat. Ephedra is widely used by athletes as a performance-enhancing drug, despite a lack of evidence that it improves athletic performance. Ephedra may also be used as a precursor in the illicit manufacture of methamphetamine. Ephedra has been used as a weight-loss aid, sometimes in combination with aspirin and caffeine. Some studies in regulated and supervised environments have shown that ephedra is effective for marginal short-term weight loss (0.9 kg/month more than the placebo), although it was unclear whether such weight loss is maintained. However, several reports have documented a number of adverse events attributable to unregulated ephedra supplements. Adverse effects of ephedra consumption may include severe skin reactions, irritability, nervousness, dizziness, trembling, headache, insomnia, profuse perspiration, dehydration, itchy scalp and skin, vomiting, and hyperthermia. More serious potential side effects include irregular heartbeat, seizures, heart attack, stroke, and death.〔(【引用サイトリンク】 Ephedra information )〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「ephedra」の詳細全文を読む スポンサード リンク
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