Bye C, Hill H M, Hughes D T, Peck A W
Eur J Clin Pharmacol. 1975;8(1):47-53. doi: 10.1007/BF00616414.
Plasma concentrations of L(+)pseudoephedrine administered in clinically used dosages were determined by gas liquid chromatography using a nitrogen sensitive detector. They were measured after administered of an immediate release formulation (Sudafed) given in either a single dose of 180 mg, or three divided doses of 60 mg, and also after administration of two different sustained release preparations containing 180 mg. Ten subjects each received five treatment regimes, administration being ordered in a balanced design based on 2 five sided Latin squares. Significant differences were found between plasma concentrations and rates of urinary excretion of L(+)pseudoephedrine following administration of the different preparations. Peak plasma concentrations were greatest after 180 mg of the immediate release preparation while more sustained elevations of concentration followed administration of both sustained release preparations and the immediate release preparation in repeated doses. Despite these differences in plasma concentration significant differences in heart rate, blood pressure, or subjective ratings of mental state rarely occured, and the reasons for this are discussed. In a second study, one of the sustained release preparations was administered to 10 subjects at a dose of 180 mg twice daily for two weeks, and plasma concentrations and effects were measured. L(+)pseudoephedrine plasma levels reached a plateau in 3 days producing increased heart rate initially insomnia occurred but this disappeared after 3 days.
采用氮敏感检测器的气相色谱法测定了临床常用剂量下L(+)伪麻黄碱的血浆浓度。在给予速释制剂（Sudafed）后进行测量，速释制剂的给药方式为单次服用180mg或分三次服用，每次60mg，还在给予两种含180mg的不同缓释制剂后进行测量。10名受试者每人接受五种治疗方案，给药按照基于两个五阶拉丁方的平衡设计进行安排。在给予不同制剂后，L(+)伪麻黄碱的血浆浓度和尿排泄率之间存在显著差异。180mg速释制剂给药后血浆浓度峰值最高，而在给予缓释制剂和重复给药的速释制剂后，浓度出现更持久的升高。尽管血浆浓度存在这些差异，但心率、血压或精神状态主观评分很少出现显著差异，并对此原因进行了讨论。在第二项研究中，将其中一种缓释制剂以180mg的剂量每日两次给予10名受试者，持续两周，并测量血浆浓度和效应。L(+)伪麻黄碱血浆水平在3天内达到平稳状态，最初心率增加，出现失眠，但3天后消失。
