Dig and weight

 Q; Digoxin should be given based on (select one)

A) adjusted body weight

B) actual body weight

C) ideal body weight

Answer: C

There are four major determinants of digoxin dosing and subsequently its toxicity 

• kidney function 
• ideal body weight
• drug interaction
• electrolyte balance

The objective of this question is to highlight the narrow therapeutic index of digoxin. 

There are other factors that may contribute to "dig toxicity". Digoxin should be avoided in patients with various atrioventricular (AV) blocks. Electrolyte imbalance such as hypokalemia, hypomagnesemia, and hypercalcemia increases the risk of digoxin-related arrhythmia. ​

Hypothyroidism is also considered a risk factor for digoxin toxicity..

#pharmacology

#cardiology

References:

1. DiDomenico RJ, Bress AP, Na-Thalang K, et al. Use of a simplified nomogram to individualize digoxin dosing versus standard dosing practices in patients with heart failure. Pharmacotherapy 2014; 34:1121. 

2. Bauman JL, DiDomenico RJ, Viana M, Fitch M. A method of determining the dose of digoxin for heart failure in the modern era. Arch Intern Med 2006; 166:2539.