Bussemer T, Otto I, Bodmeier R
College of Pharmacy, Freie Universität Berlin, Germany.
Crit Rev Ther Drug Carrier Syst. 2001;18(5):433-58.
Delivery systems with a pulsatile-release pattern are receiving increasing interest for the development of drugs for which conventional controlled drug-release systems with a continuous release are not ideal. These drugs often have a high first-pass effect or special chronopharmacological needs. A pulsatile-release profile is characterized by a time period of no release (lag time) followed by a rapid and complete drug release. Pulsatile drug-delivery systems can be classified into site-specific systems in which the drug is released at the desired site within the intestinal tract (e.g., the colon), or time-controlled devices in which the drug is released after a well-defined time period. Site-controlled release is usually controlled by environmental factors, like the pH or enzymes present in the intestinal tract, whereas the drug release from time-controlled systems is controlled primarily by the delivery system and, ideally, not by the environment. This review covers various single- and multiple-unit oral pulsatile drug-delivery systems with an emphasis on time-controlled drug-release systems.
对于那些传统的持续释放型控释药物系统不理想的药物开发而言，具有脉冲释放模式的给药系统正受到越来越多的关注。这些药物通常具有较高的首过效应或特殊的时辰药理学需求。脉冲释放曲线的特征是有一段无释放的时间段（滞后时间），随后是药物的快速完全释放。脉冲式给药系统可分为在肠道内所需部位（如结肠）释放药物的部位特异性系统，或在明确规定的时间段后释放药物的时间控制装置。部位控释通常由环境因素控制，如肠道内的pH值或酶，而时间控制型系统的药物释放主要由给药系统控制，理想情况下不受环境影响。本综述涵盖了各种单单元和多单元口服脉冲式给药系统，重点是时间控制型药物释放系统。
