Kaufmann G, Neumann P
Schweiz Med Wochenschr. 1977 Nov 26;107(47):1695-9.
In patients of a cardiological practice, 121 digoxin serum concentrations were determined by radioimmunoassay (RIA). Some drugs were suspected of interfering with the RIA or with the pharmacokinetics of digoxin. Patients having such additional drugs or patients with elevated serum creatinine were not included. The daily maintenance dose of digoxin was roughly adjusted to body weight. Patients with 0.5 mg digoxin daily showed unexpectedly low serum digoxin levels not fully explained by the relatively high body weight. This dose group was not included in the following correlations. At a maintenance dose of 0.25 and 0.375 mg digoxin and in the age groups 40-69 years (n = 66) there was an approximately inverse proportionality between serum digoxin concentration (per 0.25 mg digoxin daily) and body weight. When all age classes from 20 to 89 years were included (n = 96), a week positive correlation between serum digoxin concentration (per 0.25 mg digoxin daily and per 69.28 kg body weight) and age was found. A similar positive correlation resulted between serum digoxin concentration (per 0.25 mg digoxin daily) and the reciprocal of the nomographically determined creatinine clearance, always within the normal serum creatinine range. Based on these correlations, two simplified formulas are presented to predict the serum concentration and therapeutic maintenance dose of digoxin. The formulas are valid for the normal serum creatinine range and for digoxin tablets of optimal bioavailability.
在一个心脏病科门诊的患者中，通过放射免疫分析法（RIA）测定了121份地高辛血清浓度。怀疑某些药物会干扰RIA或地高辛的药代动力学。服用此类附加药物的患者或血清肌酐升高的患者未纳入研究。地高辛的每日维持剂量大致根据体重进行调整。每日服用0.5mg地高辛的患者血清地高辛水平意外偏低，相对较高的体重并不能完全解释这一现象。该剂量组未纳入以下相关性分析。在维持剂量为0.25mg和0.375mg地高辛且年龄在40 - 69岁的患者中（n = 66），血清地高辛浓度（每日每0.25mg地高辛）与体重之间大致呈反比例关系。当纳入所有20至89岁的年龄组时（n = 96），发现血清地高辛浓度（每日每0.25mg地高辛和每69.28kg体重）与年龄之间存在微弱的正相关。在血清肌酐正常范围内，血清地高辛浓度（每日每0.25mg地高辛）与根据列线图测定的肌酐清除率的倒数之间也呈现出类似的正相关。基于这些相关性，给出了两个简化公式来预测地高辛的血清浓度和治疗维持剂量。这些公式适用于血清肌酐正常范围以及生物利用度最佳的地高辛片剂。
