Bartow R A, Brogden R N
Adis International Limited, Auckland, New Zealand.
Drugs. 1998 Feb;55(2):303-22. doi: 10.2165/00003495-199855020-00016.
Formoterol, a selective beta 2-adrenoceptor agonist, produces effective dose-proportional bronchodilation, which persists for up to 12 hours, in patients with reversible obstructive respiratory disease. Bronchodilation is significant within minutes of inhalation, maximal within 2 hours, and at therapeutic doses is equivalent to that produced by standard doses of traditional beta 2-agonists. In single-dose studies comparing the two long-acting beta 2-agonists formoterol and salmeterol, significant bronchodilation is achieved more rapidly with formoterol than salmeterol. Duration of bronchodilation is similar with both drugs. The therapeutic efficacy of inhaled formoterol has been equal to or greater than that of salbutamol (albuterol), fenoterol and terbutaline in both short and long term clinical trials. Formoterol reduces symptoms of nocturnal asthma and reduces the need for rescue medication compared with salbutamol. Recent studies have shown that the addition of inhaled formoterol 12 or 24 micrograms twice daily to existing inhaled corticosteroid regimens improves lung function and reduces asthma symptoms compared with placebo. In one well designed study, the frequency of severe exacerbations of asthma over 12 months was decreased by adding formoterol to existing regimens of inhaled corticosteroids. Tolerance to the bronchodilator response of formoterol has not been observed in long term clinical trials. Because of its long duration of action, formoterol offers significant therapeutic advantages over shorter-acting beta 2-agonists in the treatment of nocturnal and exercise-induced asthma. Formoterol is effective in preventing exercise-induced asthma in adults and children and confers significantly more protection than salbutamol when administered 3 and 12 hours before exercise. In general, inhaled formoterol is well tolerated. The most commonly reported adverse effects, tremor and palpitations, are those traditionally associated with the use of beta 2-agonists. Oral formoterol and high doses of inhaled formoterol are associated with more adverse events than are the recommended doses of 6 to 24 micrograms. Formoterol is currently recommended for use as an alternative to increasing inhaled steroid dosage in patients whose symptoms are inadequately controlled despite therapy with low to moderate doses of inhaled steroids and intermittent short-acting beta 2-agonists, and results of recent studies support therapeutic guidelines. Long term clinical studies comparing formoterol and salmeterol have not yet been published. Further studies to evaluate the earlier use of formoterol in patients with mild to moderate asthma are needed to determine the role and long term safety of formoterol in the management of asthma.
福莫特罗是一种选择性β2肾上腺素能受体激动剂，可使可逆性阻塞性呼吸道疾病患者产生有效的剂量依赖性支气管扩张，这种扩张作用可持续长达12小时。吸入后数分钟内支气管扩张作用显著，2小时内达到最大效果，治疗剂量时其效果与标准剂量的传统β2激动剂相当。在比较两种长效β2激动剂福莫特罗和沙美特罗的单剂量研究中，福莫特罗比沙美特罗能更快地实现显著的支气管扩张。两种药物的支气管扩张持续时间相似。在短期和长期临床试验中，吸入福莫特罗的治疗效果等于或优于沙丁胺醇（舒喘灵）、非诺特罗和特布他林。与沙丁胺醇相比，福莫特罗可减轻夜间哮喘症状并减少急救药物的使用。最近的研究表明，与安慰剂相比，在现有的吸入性糖皮质激素治疗方案中每日两次添加12或24微克吸入性福莫特罗可改善肺功能并减轻哮喘症状。在一项精心设计的研究中，在现有的吸入性糖皮质激素治疗方案中添加福莫特罗可降低12个月内哮喘严重加重的频率。长期临床试验中未观察到对福莫特罗支气管扩张反应的耐受性。由于其作用持续时间长，在治疗夜间和运动诱发的哮喘方面，福莫特罗比短效β2激动剂具有显著的治疗优势。福莫特罗对预防成人和儿童运动诱发的哮喘有效，在运动前3小时和12小时给药时，其提供的保护作用比沙丁胺醇显著更强。一般来说，吸入福莫特罗耐受性良好。最常报告的不良反应是震颤和心悸，这些是传统上与使用β2激动剂相关的不良反应。口服福莫特罗和高剂量吸入福莫特罗比推荐剂量6至24微克的不良反应更多。目前推荐福莫特罗用于尽管使用了低至中等剂量的吸入性糖皮质激素和间歇性短效β2激动剂治疗但症状仍控制不佳的患者，作为增加吸入性糖皮质激素剂量的替代药物，近期研究结果支持这一治疗指南。比较福莫特罗和沙美特罗的长期临床研究尚未发表。需要进一步研究以评估福莫特罗在轻度至中度哮喘患者中的早期使用情况，以确定福莫特罗在哮喘管理中的作用和长期安全性。
