Bioavailability and elimination of digitoxin in patients with hepatorenal insufficiency

Abstract Following administration of digitoxin, 1 mg intravenously, the pharmacokinetics of this glycoside were studied in eight healthy volunteers and in eight patients with hepatorenal insufficiency (mean creatinine clearance 19.6 ± 2.9 ml/min; antipyrine clearance 25.6 ± 3.2 ml/min; X ± SEM). Liver cirrhosis of the patients was confirmed by liver biopsy. Plasma protein binding of digitoxin ( X ± SEM) was 95.1 ± 0.7% in the patients and 95.6 ± 1.2% in the volunteers (NS). Total body clearance of digitoxin was 0.0530 ± 0.0040 ml/min/kg of body weight in the patients and 0.0547 ± 0.0043 ml/min/kg of body weight in the healthy subjects (NS). When elimination half-lives of the patients and the volunteers were compared, there was also no significant difference (7.0 ± 0.77 days in the patient group and 7.8 ± 0.8 days in the volunteers). Our data concerning digitoxin kinetics in patients with hepatorenal insufficiency do not indicate an accumulation of the drug in these patients.