Digoxin

DOSAGE & ADMINISTRATION Digoxin dose is based on patient-specific factors (age, lean body weight, renal function, etc.). See full prescribing information. Monitor for toxicity and therapeutic effect. 2.1 Important Dosing and Administration Information In selecting a digoxin dosing regimen, it is important to consider factors that affect digoxin blood levels (e.g., body weight, age, renal function, concomitant drugs) since toxic levels of digoxin are only slightly higher than therapeutic levels. Dosing can be either initiated with a loading dose followed by maintenance dosing if rapid titration is desired or initiated with maintenance dosing without a loading dose. Consider interruption or reduction in digoxin dose prior to electrical cardioversion . Use digoxin solution to obtain the appropriate dose in infants, young pediatric patients, or patients with very low body weight. 2.2 Loading Dosing Regimen in Adults and Pediatric Patients For adults and pediatric patients if a loading dosage is to be given, administer half the total loading dose initially, then ¼ the loading dose every 6-8 hours twice, with careful assessment of clinical response and toxicity before each dose.

Dosing in Adults and Pediatric Patients Over 10 Years Old The maintenance dose is based on lean body weight, renal function, age, and concomitant products . The recommended starting maintenance dose in adults and pediatric patients over 10 years old with normal renal function is given in Table 2. Doses may be increased every 2 weeks according to clinical response, serum drug levels, and toxicity. Table 2. Recommended Starting Digoxin Maintenance

Dosage in Adults and Pediatric Patients Over 10 Years Old Age Total Oral Maintenance Dose, mcg/kg/day (given once daily) Adults and pediatric patients over 10 years 3.4-5.1 mcg = microgram Table 3 provides the recommended (once daily) maintenance dose for adults and pediatric patients over 10 years old (to be given once daily) according to lean body weight and renal function. The doses are based on studies in adult patients with heart failure. Alternatively, the maintenance dose may be estimated by the following formula (peak body stores lost each day through elimination): Total Maintenance Dose = Loading Dose (i.e., Peak Body Stores) x % Daily Loss/100 (% Daily Loss = 14 + Creatinine clearance/5) Reduce the dose of digoxin in patients whose lean weight is an abnormally small fraction of their total body mass because of obesity or edema. Table 3.

Dosing in Pediatric Patients Less Than 10 Years Old The starting maintenance dose for heart failure in pediatric patients less than 10 years old is based on lean body weight, renal function, age, and concomitant products . The recommended starting maintenance dose for pediatric patients between 5 years and 10 years old is given in Table 4. These recommendations assume the presence of normal renal function. Table 4. Recommended Starting Digoxin Oral Maintenance

Dosage in Pediatric Patients between 5 and 10 Years Old Age Oral Maintenance Dose, mcg/kg/dose 5 years to 10 years 3.2-6.4 Twice daily Table 5 provides average daily maintenance dose requirements for pediatric patients between 5 and 10 years old (to be given twice daily) with heart failure based on age, lean body weight, and renal function. Table 5. Recommended Maintenance Dose (in micrograms given TWICE daily) of Digoxin in Pediatric Patients between 5 and 10 Years of Agea Based upon Lean Body Weight and Renal Function a,b Corrected Creatinine Clearancec Lean Body Weight Number of Days Before Steady State Achieved d kg 20 30 40 50 60 10 mL/min - 62.5 62.5* 125 125 19 20 mL/min 62.5 62.5 125 125 125 16 30 mL/min 62.5 62.5* 125 125 187.5 14 40 mL/min 62.5 62.5* 125 187.5 187.5 13 50 mL/min 62.5 125 125 187.5 187.5 12 60 mL/min 62.5 125 125 187.5 250 11 70 mL/min 62.5 125 187.5 187.5 250 10 80 mL/min 62.5* 125 187.5 187.5 250 9 90 mL/min 62.5* 125 187.5 250 250 8 100 mL/min 62.5* 125 187.5 250 312.5 7 a Recommended are doses to be given twice daily. b The doses are rounded to the nearest dose possible using whole digoxin tablets.