title: Digoxin dosage in renal insufficiency: impracticality of basing it on the creatinine clearance, body weight and volume of distribution.
abstract: Previous dosing schedules for digoxin in renal failure have considered the decrease in the elimination rate constant but not the decrease in the volume of distribution. A dosing schedule based on the creatinine clearance, body weight and volume of distribution has been developed from pharmacokinetic data taken from the literature. Its validity was tested in a clinical study of 35 patients with chronic renal insufficiency not requiring dialysis. The dosing schedule resulted in correct digitalization expressed as a steady state plasma digoxin concentration in the therapeutic range (0.5-2.0 ng/ml) in 25 out of 27 patients (93%). However, of 82 possible candidates for the study, it could not be performed in 47 (57%). The high drop-out rate was mainly due to the complicated dosing schedule and to the difficulty of repeatedly measuring creatinine clearance on a routine basis. Therefore, safe dosing of digoxin in renal insufficiency does not seem to be feasible in practice. Digitoxin may be a better alternative.
mesh_terms: D000328:Adult; D000368:Aged; D001835:Body Weight; D003404:Creatinine / Q000378:metabolism; D004077:Digoxin / Q000008:administration & dosage* / Q000009:adverse effects / Q000097:blood; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000378:metabolism*; D007700:Kinetics; D008297:Male; D008875:Middle Aged
chemical_list: D004077:Digoxin; D003404:Creatinine