[Pharmacokinetics of digoxin and methyldigoxin in patients with acute hepatitis (author's transl)]

After i.v. application of 3h-digoxin or 3H-methyldigoxin to 5 healthy volunteers and 5 patients with acute hepatitis, respectively (0.75 mg daily for 3 days and 0.375 for the following 2 days) total radioactivity in urine and plasma were determined. Chloroform-soluble and -insoluble glycosides were separated and the chloroform-soluble fraction was determined by TLC. 3 days after methyldigoxin application plasma levels reached toxic values in the patient group (2.73 +/- 0.48 ng/ml), whereas in patients receiving digoxin a mean plasma level of 0.91 +/- 0.21 ng/ml was obtained. During the first 24 hours following administration of digoxin 44 +/- 12% of the dose were recovered in urine of control subjects and 48 +/- 13% in patients with acute hepatitis, after methyldigoxin 34 +/- 5% and 34 +/- 8%, respectively. Metabolism of digoxin in patients with acute hepatitis was unaltered, whereas a diminished demethylation rate of methyldigoxin could be observed. 16 patients with acute hepatitis and 7 healthy volunteers received unlabelled digoxin p.o. as maintenance dose. Plasma glycoside concentrations were studied by radioimmunoassay. The average glycoside plasma concentrations were 0.59 +/- 0.21 ng/ml and 0.63 +/- 0.24 ng/ml, respectively.