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Halothane (trademarked as Fluothane) is a general anesthetic that is inhaled. Its IUPAC name is 2-bromo-2-chloro-1,1,1-trifluoroethane. It is the only inhalational anesthetic containing bromine. It is colorless and pleasant-smelling, but unstable in light. It is packaged in dark-colored bottles and contains 0.01% thymol as a stabilizing agent. It is on the WHO Model List of Essential Medicines, the most important medications needed in a basic health system. Its use in developed countries has been mostly superseded by newer agents such as sevoflurane, isoflurane, and desflurane. As of 2014 it cost about 22 to 52 USD for a 250 ml bottle.〔(【引用サイトリンク】url=http://erc.msh.org/dmpguide/resultsdetail.cfm?language=english&code=HLT250I&s_year=2014&year=2014&str=&desc=Halothane&pack=new&frm=LIQUID&rte=INH&class_code2=01%2E1%2E1%2E&supplement=&class_name=%2801%2E1%2E1%2E%29Inhalational%20medicines%3Cbr%3E )〕 ==Medical uses== It is a potent anesthetic with a MAC of 0.74%. Its blood/gas partition coefficient of 2.4 makes it an agent with moderate induction and recovery time. It is not a good analgesic and its muscle relaxation effect is moderate. ==Side effects== In rare cases, repeated exposure to halothane in adults was noted to result in severe liver injury. This occurred in about one in 10,000 exposures. The resulting syndrome was referred to as halothane hepatitis, and is thought to result from the metabolism of halothane to trifluoroacetic acid via oxidative reactions in the liver. About 20% of inhaled halothane is metabolized by the liver and these products are excreted in the urine. The hepatitis syndrome had a mortality rate of 30% to 70%. Concern for hepatitis resulted in a dramatic reduction in the use of halothane for adults and it was replaced in the 1980s by enflurane and isoflurane. By 2005, the most common volatile anesthetics used were isoflurane, sevoflurane, and desflurane. Since the risk of halothane hepatitis in children was substantially lower than in adults, halothane continued to be used in pediatrics in the 1990s as it was especially useful for inhalation induction of anaesthesia . However, by 2000, sevoflurane, excellent for inhalation induction, had largely replaced the use of halothane in children. Halothane sensitises the heart to catecholamines, so it is liable to cause cardiac arrhythmias, occasionally fatal, particularly if hypercapnia has been allowed to develop. This seems to be especially problematic in dental anaesthesia. Like all the potent inhalational anaesthetic agents, it is a potent trigger for malignant hyperthermia. Similarly, in common with the other potent inhalational agents, it relaxes uterine smooth muscle and this may increase blood loss during delivery or termination of pregnancy. 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「Halothane」の詳細全文を読む スポンサード リンク
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