Digitalis Glycosides

Abstract

Digoxin Absorption: mainly in the proximal small intestine, bioavailability of 80 % Volume of distribution: 5.6 L/kg; slow but widespread dissemination into the tissues, particularly the myocardium, kidneys, and skeletal muscle; duration of distribution (2-6 h) Protein binding: 20-30 % Active metabolites: digoxigenin, digoxigenin mono-digitoxiside and bis-digitoxiside Predominant elimination route: kidney Elimination: as unaltered in urine (93 %) Elimination half-life: mean 40 h, range 20-50 h Digitoxin Absorption: in the stomach (15 %) and proximal small intestine (85 %), bioavailability of >90 % Volume of distribution: 0.56 L/kg; rapid and widespread dissemination into the tissues due to its high lipophilic properties Protein binding: 95 % Active metabolites: digoxin (minor pathway) Predominant elimination route: liver (75-90 %) Elimination: as unchanged in the feces and urine Elimination half-life: 4.9-8.1 days