Digoxin elimination

Verapamil Inhibits AV nodal conduction by slowing AV nodal conduction and prolonging AV nodal refractoriness 1. 5-10 mg IV over 2-3 minutes 2. If necessary, an additional dose of 5-1 0 mg may be administered 30 minutes later 120-360 mg/day Inhibits digoxin elimination... 

Digoxin 1. Vagal stimulation 2. Direct AV nodal inhibition 0.25 mg IV every 2 hours, up to 1.5 mg Amiodarone and verapamil (inhibit digoxin elimination)... 

B. Aspirin was competing for protein binding with digoxin, leading to increased concentrations of free digoxin and thus more free digoxin eliminated by the kidneys. 

SCHEME 11.26 Reduction of the side chain of digoxin eliminates pharmacologic activity. 

Ibanez C, Carcas AJ, Frias J, Abad F. Activated charcoal increases digoxin elimination in patients. Int J Cardiol 1995 48(l) 27-30. 

The maintenance dose can then be calculated based on the amount of the loading dose (or total body stores) that is eliminated each day." The amount of digoxin eliminated daily can be calculated by Equation 8.9. 

Not fully understood. The authors of the studies concluded that ciclosporin has no specific inhibitory effect on the renal elimination of digoxin, but that it causes a non-specific reduction in renal function after acute administration, which reduces digoxin elimination. Conversely, another study in animals suggested that ciclosporin can reduce the secretion of digoxin by the kidney tubular cells by inhibiting P-glycoprotein. ... 

Because digitoxin is a nonpolar, lipophilic glycoside, absorption from the GI tract is complete. About 90% of the dmg in plasma is tightly bound to protein. It is metabolized in the Hver to many metaboHtes, including digoxin which is the only pharmacologically active metaboHte. The dmg is excreted via the bile into feces. The elimination half-life of digitoxin is seven to nine days (87). 

Digoxin is more rapidly eliminated and thereby, possible adverse or toxic effects last for a shorter time. 

Smith, T.W. Lloyd, B.L. Spicer, N. and Haber, E. Immuno-genicity and kinetics of distribution and elimination of sheep digoxin-specific IgG and Fab fragments in the rabbit and baboon. Clin Exp Immunol 36 384-396, 1979. 

Amiodarone 5-7 mg/kg IV over 30-60 minutes 700-1200 mg over 24 hours Inhibits elimination of digoxin and warfarin... 

Rapid digitalization with a loading dose Peak digoxin body stores of 8 to 12 mcg/kg should provide therapeutic effect with minimum risk of toxicity in most patients with heart failure and normal sinus rhythm. Because of altered digoxin distribution and elimination, projected peak body stores for patients with renal insufficiency should be conservative (ie, 6 to 10 mcg/kg see Precautions). 

Drugs that may be affected by trospium include those eliminated by active tubular secretion (eg, digoxin, procainamide, pancuronium, morphine, vancomycin, metformin, and tenofovir). 

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