Cedarbaum J M, Kutt H, McDowell F H
Department of Neurology, Cornell University Medical College, White Plains, NY.
Neurology. 1989 Nov;39(11 Suppl 2):38-44; discussion 59.
Seventeen patients with advanced Parkinson's disease who had fluctuations in motor performance while taking standard Sinemet (STD) 25/100 underwent daylong pharmacokinetic and clinical observation studies while taking both STD and Sinemet CR, a new controlled-release formulation containing 50 mg carbidopa and 200 mg levodopa. During treatment with Sinemet CR, there was an increase in the interdose interval, a reduction in the number of medication doses taken each day, an increase in total "on" time, and a reduction in the number of "off" episodes. Total daily levodopa intake was greater with Sinemet CR, although the bioavailability of levodopa and carbidopa from the two preparations was equivalent. The variability in plasma levodopa levels was significantly less with Sinemet CR. The slower release of drug from Sinemet CR was reflected in a prolongation of the Tmax for levodopa and a prolongation of the interval from Tmax to the succeeding trough levodopa level. Clinically, peak antiparkinsonian effect occurred later and lasted longer with the CR preparation.
17名晚期帕金森病患者在服用标准息宁（STD）25/100时运动表现有波动，在同时服用STD和息宁控释片（Sinemet CR，一种含有50毫克卡比多巴和200毫克左旋多巴的新型控释制剂）期间接受了为期一天的药代动力学和临床观察研究。在使用息宁控释片治疗期间，给药间隔时间增加，每天服用的药物剂量减少，总的“开”期时间增加，“关”期发作次数减少。息宁控释片的每日左旋多巴总摄入量更高，尽管两种制剂中左旋多巴和卡比多巴的生物利用度相当。息宁控释片使血浆左旋多巴水平的变异性显著降低。息宁控释片中药物释放较慢表现为左旋多巴的达峰时间延长以及从达峰时间到随后左旋多巴谷浓度水平的间隔时间延长。临床上，控释制剂的抗帕金森病峰值效应出现较晚且持续时间更长。
