From the Guidelines
Administration of Digoxin in Patients with Impaired Renal Function
Digoxin can be administered in patients with impaired renal function (IRF), but it should be used with caution.
- The dose of digoxin should be reduced in patients with IRF, with a typical starting dose of 0.125 mg orally every 24-48 hours 1.
- Patients with severe renal impairment (creatinine clearance less than 10 mL/min) should not be initiated on digoxin therapy.
- For patients with mild to moderate renal impairment (creatinine clearance 10-50 mL/min), the dose of digoxin should be closely monitored and adjusted based on serum digoxin levels and clinical response.
- Serum digoxin levels should be monitored regularly to avoid toxicity, aiming for a level between 0.5-1.0 ng/mL 1.
- Factors such as age (>70 years), low lean body mass, and concomitant use of certain medications (e.g., amiodarone, beta blockers) should also be considered when initiating digoxin therapy in patients with IRF 1.
- The goal is to balance the potential benefits of digoxin therapy with the risks of toxicity, particularly in patients with impaired renal function.
From the FDA Drug Label
Digoxin is primarily excreted by the kidneys; therefore, patients with impaired renal function require smaller than usual maintenance doses of digoxin Because of the prolonged elimination half-life, a longer period of time is required to achieve an initial or new steady-state serum concentration in patients with renal impairment than in patients with normal renal function If appropriate care is not taken to reduce the dose of digoxin, such patients are at high risk for toxicity, and toxic effects will last longer in such patients than in patients with normal renal function.
Administration in Patients with Impaired Renal Function (IRF) is possible, but the dose of digoxin should be reduced to avoid toxicity. The maintenance dose should be based on the patient's renal function, with conservative peak body stores (i.e., 6 to 10 mcg/kg) recommended for patients with renal insufficiency 2.
- The dose may be calculated using the formula: Maintenance Dose = Peak Body Stores x % Daily Loss/100, where % Daily Loss = 14 + Ccr/5 (Ccr is creatinine clearance) 2.
- Table 5 provides average daily maintenance dose requirements of digoxin for patients with heart failure based on lean body weight and renal function 2.
From the Research
Administration of Digoxin in Patients with Impaired Renal Function
- Digoxin can be administered in patients with impaired renal function (IRF), but with caution and careful monitoring of serum levels 3, 4, 5, 6, 7
- The pharmacokinetics of digoxin are altered in patients with renal impairment, with reduced total body clearance and increased steady-state plasma concentrations 3, 5
- The volume of distribution of digoxin is smaller in patients with severe renal failure, requiring adjustment of the loading dose 3, 5
- Maintenance dosage regimens must also be adjusted in patients with impaired renal function to avoid toxicity 3, 4
Dosage Adjustments
- Loading doses of digoxin may need to be reduced in patients with severe renal impairment to avoid high plasma concentrations and potential toxicity 4
- Maintenance doses of digoxin should be adjusted based on the patient's renal function, with lower doses required in patients with more severe impairment 3, 4, 6
Monitoring and Safety
- Patients with impaired renal function are at increased risk of digoxin toxicity, and careful monitoring of serum levels and clinical symptoms is essential 6, 7
- Digoxin-specific Fab antibody fragments can be effective in treating digoxin intoxication in patients with renal disease, but may require longer observation periods due to the risk of rebound toxicity 7