Morning-evening administration time differences in digoxin kinetics in healthy young subjects


Erol K., Kilic F. S. , Batu O., Yildirim E.

CHRONOBIOLOGY INTERNATIONAL, vol.18, no.5, pp.841-849, 2001 (Journal Indexed in SCI) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 18 Issue: 5
  • Publication Date: 2001
  • Doi Number: 10.1081/cbi-100107519
  • Title of Journal : CHRONOBIOLOGY INTERNATIONAL
  • Page Numbers: pp.841-849

Abstract

Digoxin, frequently used in the treatment of congestive heart failure, has a very narrow therapeutic index. We studied the differences in digoxin pharmacokinetics when ingested in the morning versus evening. A single digoxin (0.25 mg) dose was given orally to the same group of 10 diurnally active healthy (6 male and 4 female) volunteers in the morning at 08:00 and evening at 20:00 in separate experiments scheduled 2 weeks apart. Blood samples were collected at specific times for 48h after each timed dose; digoxin was determined by radioimmunoassay (RIA). Maximum plasma concentration C-max; T-max, the time to reach C-max; area under plasma concentration curve AUC; and elimination half-time T-1/2 of digoxin were determined. T-max was statistically significantly shorter (54 min) following 08:00 dosing compared to 20:00 dosing (96 min). Although the Cm was higher after morning than evening dosing, it was not significantly so. No other parameter of digoxin pharmacokinetics except Tm exhibited administration time dependency.