Digoxin Toxicity : Evaluation in Clinical Practice with Pharmacokinetic Correlations

Area of Science:

• Pharmacokinetics and Pharmacodynamics
• Clinical Toxicology

Background:

• Digoxin is a critical medication for heart conditions, but its narrow therapeutic index poses a risk of toxicity.
• Understanding digoxin pharmacokinetics is crucial for optimizing patient outcomes and minimizing adverse events.

Purpose of the Study:

• To evaluate digoxin pharmacokinetic parameters using Bayesian estimation in a cohort of 60 patients.
• To identify clinical factors associated with an increased risk of digoxin toxicity.

Main Methods:

• Retrospective analysis of 60 patients with measured serum digoxin concentrations.
• Collection of demographic, clinical, laboratory, and medication data.
• Bayesian estimation of individual pharmacokinetic parameters using Abbottbase Pharmacokinetic Systems.

Main Results:

• Digoxin toxicity was observed in 46% of patients, with higher serum concentrations in those affected.
• Older age, elevated serum creatinine, lower body weight, and altered volume of distribution, clearance, and half-life were associated with toxicity.
• Optimal dose estimation indicated a need for 3.5-fold lower doses in intoxicated patients to achieve therapeutic levels.

Conclusions:

• Elevated digoxin concentrations are linked to toxicity, with older age being a significant risk factor.
• Monitoring serum digoxin levels is essential for confirming suspected digitalis toxicity.
• Bayesian pharmacokinetic analysis provides valuable insights for personalized digoxin dosing and toxicity risk assessment.