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Zolpidem (brand names Ambien, Ambien CR, Intermezzo, Stilnox, Stilnoct, Sublinox, Hypnogen, Lunata, Zonadin, Sanval, Zolsana and Zolfresh) is a prescription medication used for the treatment of insomnia and some brain disorders. It is a short-acting nonbenzodiazepine hypnotic of the imidazopyridine class that potentiates GABA, an inhibitory neurotransmitter, by binding to GABAA receptors at the same location as benzodiazepines. It works quickly, usually within 15 minutes, and has a short half-life of two to three hours. Zolpidem has not adequately demonstrated effectiveness in maintaining sleep, unless delivered in a controlled-release (CR) form. However, it is effective in initiating sleep. Its hypnotic effects are similar to those of the benzodiazepine class of drugs, but it is molecularly distinct from the classical benzodiazepine molecule and is classified as an imidazopyridine. Flumazenil, a benzodiazepine receptor antagonist, which is used for benzodiazepine overdose, can also reverse zolpidem's sedative/hypnotic and memory-impairing effects. Zolpidem has slight muscle relaxant and anticonvulsant properties, but has not been approved for use in muscle relaxation or seizure prevention. This is because the dosage of drug needed to cause muscle relaxation is 10 times the sedating dose, and the dosage needed for preventing seizures is 20 times the sedating dose; high dosages are more likely to cause unpleasant side effects such as hallucinations and amnesia. Contrary to early studies, more recent research has indicated that zolpidem is in fact a potent anticonvulsant. The anticonvulsant effects are not realized until the normal dosage range has been surpassed (meaning sedation would still be a major side effect) but the threshold for this effect is now believed to be considerably lower than original estimates. The United States patent for zolpidem was held by the French pharmaceutical corporation Sanofi-Aventis. On April 23, 2007, the U.S. Food and Drug Administration (FDA) approved 13 generic versions of zolpidem tartrate.〔(【引用サイトリンク】 FDA Approves First Generic Versions of Ambien (Zolpidem Tartrate) for the Treatment of Insomnia )〕 Zolpidem is available from several generic manufacturers in the UK, as a generic from Sandoz in South Africa and TEVA in Israel, as well as from other manufacturers such as Ratiopharm and Takeda GmbH (both Germany). On January 10, 2013, the Food and Drug Administration announced it is requiring the manufacturer of Ambien and Zolpimist to cut the recommended dosage for women in half, after laboratory studies showed that the medicines can leave patients drowsy in the morning and at risk for motor vehicle collisions. The FDA recommended that manufacturers extend the new dosage cuts to men as well, who process the drug at a faster rate; however, the reasons men and women metabolize the drugs at different rates are still unknown. In May 2013, the FDA approved label changes specifying new dosage recommendations for zolpidem products because of concerns regarding next-morning impairment. ==Medical uses== Clinicians prescribe zolpidem for short-term (usually about two to six weeks) treatment of insomnia.〔(【引用サイトリンク】 url = http://www.drugs.com/monograph/ambien.html ) 〕 Zolpidem addresses sleep-initiation problems, but is not effective in maintaining sleep.〔 Also, a 2012 NIH study showed that zolpidem's effectiveness is nearly as much due to psychological effects as to the drug itself, so "increased attention should be directed at psychological intervention of insomnia."〔 〕 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「zolpidem」の詳細全文を読む スポンサード リンク
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