Studies on digitalis. V. The influence of impaired renal function, hemodialysis, and drug interaction on serum protein binding of digitoxin and digoxin

Publisher Website
Google Scholar
Abstract
The aim of the present investigation is to study digitoxin and digoxin protein binding in patients with normal renal and hepatic function, in patients with uremia, and in patients under treatment with hemodialysis for renal failure. The binding of digitoxin and cardioactive metabolites to serum proteins was studied using equilibrium dialysis (an in vitro chemical assay) alone and in combination with a modified 86Rb method. The following values for protein binding were found: DT-3 (digitoxin), 95.7%; DT-2 (digitoxigenin-bis-digitoxoside), 96.5%; DT-1 (digitoxigenin-mono-digitoxoside), 98.7'; DT-0 (digitoxigenin), 92.7'; DG-3 (digoxin), 21.2 %; DG-2 (digoxigenin-bisdigitoxoside), 16.3%; DG-1 (digoxigenin-mono-digitoxoside), 18.5%; and DG-0 (digoxigenin), 13.3%. In vitro addition of procainamide, phenytoin, heparin, and rifampicillin did not influence the in vitro binding of digitoxin. Protein binding of digitoxin showed small individual variations in patients with normal renal and hepatic junction. Uremia per se did not influence the in vitro binding of digitoxin. There were marked changes in digitoxin and digoxin protein binding during an 8-hr hemodialysis, digitoxin binding decreasing from 97.1% to 93.7% (p < 0.0025) and digoxin binding from 23.5% to 15.4% (p < 0.05). In the uremic patient the metabolic pattern of digitoxin tended toward a decrease in protein-bound metabolites.

This publication has 0 references indexed in Scilit: