Paul Ian M, Shaffer Michele L, Yoder Katharine E, Sturgis Sarah A, Baker Mark S, Berlin Cheston M
Department of Pediatrics, Pennsylvania State University College of Medicine, Hershey, Pennsylvania, USA.
Clin Ther. 2004 Sep;26(9):1508-14. doi: 10.1016/s0149-2918(04)80297-2.
The efficacy of dextromethorphan (DM) for treating acute cough is uncertain, and its use is not supported by the American Academy of Pediatrics. Nevertheless, DM is often administered to children as an antitussive. DM dosages are based on age rather than body weight, resulting in substantial variability in the relative amount of drug administered.
The aim of this work was to determine whether a dose-response relationship existed among a group of children administered a single nocturnal dose of DM for cough due to an upper respiratory tract infection.
As part of a larger double-blind, placebo-controlled trial of over-the-counter cough medications, children received DM. The administered doses (per manufacturer recommendations) were as follows: ages 2 to 5 years, 7.5 mg; ages 6 to 11 years, 15 mg; and ages 12 to 18 years, 30 mg. This resulted in a range of 0.35 to 0.94 mg/kg per dose. Subjective parental assessments of cough and sleep were obtained using a 7-point Likert-type scale that compared symptoms after medication with symptoms during the prior night (without medication). Three dose ranges were compared as a subset analysis of the group that received DM.
Thirty-three patients (19 girls, 14 boys; median [interquartile range] age, 4.90 [2.90-6.80] years; age range, 2.10-16.50 years) received DM and completed the study. No significant differences were found for any of the outcome measures when comparing the effects of different doses of DM, but our observations suggested somewhat more symptomatic relief for patients receiving medium-dose DM (0.45 to <0.60 mg/kg per dose) or high-dose (HD) DM (0.60-0.94 mg/kg per dose) compared with low-dose DM (0.35 to <0.45 mg/kg per dose). Adverse events occurred most often in the HD group.
Although no statistically significant differences were detectable for the outcomes studied, our observations suggest the potential for improved clinical symptom control with increasing doses of DM. Our findings may further suggest that a dose of 0.5 mg/kg should be considered in future assessments of the antitussive effect of DM in pediatric studies, to balance symptomatic relief with the avoidance of adverse events.
右美沙芬（DM）治疗急性咳嗽的疗效尚不确定，美国儿科学会也不支持使用该药。然而，DM常作为止咳药用于儿童。DM的剂量是基于年龄而非体重，这导致给药的相对剂量存在很大差异。
本研究旨在确定一组因上呼吸道感染咳嗽而接受单次夜间剂量DM治疗的儿童中是否存在剂量反应关系。
作为一项更大规模的非处方止咳药双盲、安慰剂对照试验的一部分，儿童接受了DM治疗。给药剂量（按照制造商建议）如下：2至5岁儿童，7.5毫克；6至11岁儿童，15毫克；12至18岁儿童，30毫克。这导致每剂的剂量范围为0.35至0.94毫克/千克。使用7点李克特量表获得家长对咳嗽和睡眠的主观评估，该量表将用药后的症状与前一晚（未用药）的症状进行比较。作为接受DM治疗组的亚组分析，比较了三个剂量范围。
33名患者（19名女孩，14名男孩；年龄中位数[四分位间距]为4.90[2.90 - 6.80]岁；年龄范围为2.10 - 16.50岁）接受了DM治疗并完成了研究。比较不同剂量DM的效果时，在任何一项结局指标上均未发现显著差异，但我们的观察结果表明，与低剂量DM（每剂0.35至<0.45毫克/千克）相比，接受中剂量DM（每剂0.45至<0.60毫克/千克）或高剂量（HD）DM（每剂0.60 - 0.94毫克/千克）的患者症状缓解程度略高。不良事件最常发生在HD组。
尽管在所研究的结局中未检测到统计学上的显著差异，但我们的观察结果表明，随着DM剂量的增加，临床症状控制可能会有所改善。我们的研究结果可能进一步表明，在未来儿科研究中评估DM的止咳效果时，应考虑0.5毫克/千克的剂量，以在症状缓解与避免不良事件之间取得平衡。
