Artemisia annua, also known as Sweet Wormwood, Sweet Annie, Sweet Sagewort or Annual Wormwood (Chinese: 青蒿; pinyin: qīnghāo), is a common type of wormwood that is native to temperate Asia, but naturalized throughout the world. In 1971, scientists demonstrated that the plant extracts had antimalarial activity in primate models, and in 1972 the active ingredient, artemisinin (formerly referred to as arteannuin), was isolated and its chemical structure described. Artemisinin may be extracted using a low boiling point solvent such as diethylether and is found in the glandular trichomes of the leaves, stems, and inflorescences, and it is concentrated in the upper portions of plant within new growth. It is commonly used in tropical nations which can afford it, preferentially as part of a combination-cocktail with other antimalarials in order to prevent the development of parasite resistance.
Artemisinin itself is a sesquiterpene lactone with an endoperoxide bridge and has been produced semi-synthetically as an antimalarial drug. The efficacy of tea made from A. annua in the treatment of malaria is contentious. According to some authors, artemesinin is not soluble in water and the concentrations in these infusions are considered insufficient to treatment malaria. Other researchers have claimed that Artemisia annua contains a cocktail of anti-malarial substances, and insist that clinical trials be conducted to demonstrate scientifically that artemisia tea is effective in treating malaria. This simpler use may be a cheaper alternative to commercial pharmaceuticals, and may enable health dispensaries in the tropics to be more self-reliant in their malaria treatment. In 2004, the Ethiopian Ministry of Health changed Ethiopia’s first line anti-malaria drug from Fansidar, a sulfadoxine agent which has an average 36% treatment failure rate, to Coartem, a drug therapy containing artemesinin which is 100% effective when used correctly, despite a worldwide shortage at the time of the needed derivative from A. annua.
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- Räth K, Taxis K, Walz GH, et al. (1 February 2004). "Pharmacokinetic study of artemisinin after oral intake of a traditional preparation of Artemisia annua L. (annual wormwood)". Am J Trop Med Hyg 70 (2): 128–32. PMID 14993622.
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- "Malaria Update", Focus on Ethiopia, April 2005, UN-OCHA website (accessed 12 March 2009)