Extrarenal clearance, distribution volume, and elimination rate of digoxin and metildigoxin in anuric patients
Twittenhoff, W.D.; Strauch, M.; Kütemeyer, M.; Koch, K.; Schaumann, W.
International Journal of Clinical Pharmacology Therapy and Toxicology 19(9): 405-408
1981
ISSN/ISBN: 0174-4879 PMID: 7298247 Document Number: 175987
The pharmacokinetics of 3H-labeled digoxin and methyldigoxin were compared in 6 anuric patients. The following means .+-. SEM [SE of mean] were obtained: extrarenal clearance of digoxin, 43.3 .+-. 5.4 ml/min, of methyldigoxin, 30.3 .+-. 2.9 ml/min; distribution volume of digoxin, 315 .+-. 29 l, of methyldigoxin, 258 .+-. 22 l; rate constant for elimination of digoxin, 0.0086 .+-. 0.0013 h, of methyldigoxin, 0.0071 .+-. 0.0007 h. The elimination rates correspond to half-lives of 80 h for digoxin and of 97 h for methyldigoxin. From the investigations and published data a weighted mean of 47 ml/min was calculated for the extrarenal clearance of methyldigoxin. This is not significantly different from the mean extrarenal clearance of 40 ml/min reported for digoxin. A total body clearance of 40 ml/min and a daily i.v. dose of 0.1 mg correspond to an average steady-state cardiac glycoside concentration of 1.74 ng/ml.