Rietbrock N, Kuhlmann J, Vöhringer H F
Fortschr Med. 1977 Apr 14;95(14):909-15, 951-4.
The purpose of pharmacokinetics of cardiac glycosides is to study the time courses of glycosides in biological fluids, tissues and excreta. The extent of accumulation of a given dose at uniform time intervals depends only from the overall elimination rate constant. By knowing the elimination rate constant the extent to which a cardiac glycoside would accumulate in the body following a fixed dosing regimen can be calculated. The higher accumulation in the central nervous system requires a much longer time. Therefore it may be assumed that the brain is a deep compartment for cardiac glycosides and this compartment cannot be detected by analysis of plasma glycoside concentrations. Central side effects of cardiac glycosides may occur at therapeutic plasma levels. In renal disease a lower maintenance dose of digoxin and methyldigoxin should be administered or the same dose less frequently. Digitoxin does not accumulate in patients with renal failure or in anuria since the extrarenal elimination of digitoxin is much higher compared to digoxin and methyldigoxin.
强心苷类药物的药代动力学目的是研究苷类在生物体液、组织和排泄物中的时间过程。在均匀时间间隔内给定剂量的蓄积程度仅取决于总体消除速率常数。通过了解消除速率常数，就可以计算出在固定给药方案下强心苷在体内的蓄积程度。在中枢神经系统中的较高蓄积需要更长的时间。因此，可以假设大脑是强心苷的一个深部隔室，并且通过分析血浆苷浓度无法检测到这个隔室。强心苷的中枢副作用可能在治疗性血浆水平时出现。在肾脏疾病中，应给予较低维持剂量的地高辛和甲基地高辛，或者减少给药频率。洋地黄毒苷在肾衰竭患者或无尿患者中不会蓄积，因为与地高辛和甲基地高辛相比，洋地黄毒苷的肾外消除要高得多。
