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Salmeterol is a long-acting beta2-adrenergic receptor agonist drug used in the maintenance and prevention of asthma symptoms and maintenance of chronic obstructive pulmonary disease (COPD) symptoms.〔(【引用サイトリンク】url=http://www.goldcopd.org/uploads/users/files/GOLDReport_April112011.pdf )〕 Symptoms include shortness of breath, wheezing, coughing and chest tightness. It is also used to prevent breathing difficulties during exercise (exercise induced bronchospasm).〔(【引用サイトリンク】url=http://www.nlm.nih.gov/medlineplus/druginfo/meds/a695001.html#why )〕 It is marketed as Serevent in the US.〔(【引用サイトリンク】url=http://www.medicinenet.com/salmeterol/page2.htm )〕 It is available as a dry powder inhaler that releases a powdered form of the drug. It was previously available as a metered-dose inhaler (MDI) but was discontinued in the US in 2002.〔〔(【引用サイトリンク】url=http://www.fda.gov/ohrms/dockets/ac/08/briefing/2008-4398b1-04-gsk.pdf )〕 It is still available as a MDI in the UK as of 2013. ==Medical uses== Salmeterol is a long-acting beta2-adrenoceptor agonist (LABA), used in moderate to severe persistent asthma following previous treatment with a short-acting beta2-adrenoceptor agonist (SABA) such as salbutamol (albuterol). LABAs should not be used as a mono-therapy, instead, they should be used concurrently with a corticosteroid, such as beclometasone dipropionate or fluticasone propionate in the treatment of asthma to minimize serious reactions such as asthma related deaths. In chronic obstructive pulmonary disease (COPD), LABAs may be used as mono-therapy or in combination with corticosteroids. In exercise induced bronchospasm mono-therapy may be indicated in patients without persistent asthma. LABAs should not be used to treat acute symptoms.〔〔(【引用サイトリンク】url=http://www.ginasthma.org/local/uploads/files/GINA_Report_2014_Aug12.pdf )〕〔(【引用サイトリンク】url=http://www.mhra.gov.uk/Safetyinformation/DrugSafetyUpdate/CON087967 )〕 The primary noticeable difference of salmeterol from salbutamol, and other short-acting beta2-adrenoceptor agonists (SABAs), is its duration of action. Salmeterol lasts approximately 12 hours in comparison with the salbutamol, which last about 4–6 hours.〔〔 When used regularly every day as prescribed, inhaled salmeterol decreases the number and severity of asthma attacks. However, like all LABA medications, it is not for use in relieving an asthma attack that has already started. Inhaled salmeterol works like other beta 2-agonists, causing bronchodilation by relaxing the smooth muscle in the airway so as to treat the exacerbation of asthma. The long duration of action occurs by the molecules initially diffusing into the plasma membrane of the lung cells, and then slowly being released back outside the cell where they can come into contact with the beta2 adrenoceptors, with the long carbon chain forming an anchor in the membrane. Interestingly, salmeterol binding to the beta2-adrenoceptor does not induce desensitisation or internalization of receptors which may also contribute to its long therapeutic duration of action. Formoterol has been demonstrated to have a faster onset of action than salmeterol as a result of a lower lipophilicity, and has also been demonstrated to be more potent—a 12 µg dose of formoterol has been demonstrated to be equivalent to a 50 µg dose of salmeterol.〔〔(【引用サイトリンク】url=http://www.partnershiphp.org/Members/HealthEd/Asthma%20pdf/LongTermControlMeds12-adult_043010.pdf )〕 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「salmeterol」の詳細全文を読む スポンサード リンク
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