About 70 to 80% of an oral dose of digoxin is absorbed, mainly in the proximal part of the small intestine. The degree of binding to serum albumin is 20 to 30%. Digoxin is extensively distributed in the tissues, as reflected by the large volume of distribution.
Does digoxin have linear pharmacokinetics?
These results indicate that there is a linear relationship between digoxin plasma concentration and dose in patients with normal and decreased renal function. This linearity is support for dose-independent pharmacokinetics of digoxin in man.
How does digoxin work physiologically?
Digoxin induces an increase in intracellular sodium that will drive an influx of calcium in the heart and cause an increase in contractility. Cardiac output increases with a subsequent decrease in ventricular filling pressures.  AV Node Inhibition: Digoxin has vagomimetic effects on the AV node.
Is digoxin hydrophilic?
Digoxin is highly hydrophilic and the dose-effect relationship is dependent on lean body mass; dosage should be based on ideal body weight.
What are adverse effects of digoxin?
Digoxin may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
dizziness or lightheadedness.
vision changes (blurred or yellow)
What should be the bioavailability of Digoxin Tablets?
The use of pharmacokinetics to adjust the dosing regimen can reduce the incidence of digoxin toxicity.2,11–13 BIOAVAILABILITY (F) The bioavailability of digoxin tablets ranges from 0.5 to greater than 0.9. Many clinicians use a bioavailability of 0.7 to 0.8.
How long does it take for digoxin to take effect?
Pharmacokinetics: Absorption: Following oral administration, peak serum concentrations of digoxin occur at 1 to 3 hours. Absorption of digoxin from Lanoxin Tablets has been demonstrated to be 60% to 80% complete compared to an identical intravenous dose of digoxin (absolute bioavailability).
How much digoxin is in a Lanoxin tablet?
Lanoxin is supplied as 125-mcg (0.125-mg) or 250-mcg (0.25-mg) tablets for oral. administration. Each tablet contains the labeled amount of digoxin USP and the following. inactive ingredients: corn and potato starches, lactose, and magnesium stearate.
How much digoxin is eliminated by the enterohepatic cycle?
About 25 to 28% of digoxin is eliminated by nonrenal routes. Biliary excretion may rise up to 30% of a given dose, but the enterohepatic cycle seems to be of minor importance.