What is the initial dose of digoxin (digitalis glycoside) for a patient with atrial fibrillation?

From the Guidelines

The initial dose of digoxin for a patient with atrial fibrillation is 0.5 mg intravenous bolus, which can be followed by 0.75-1.5 mg over 24 hours in divided doses, with a maintenance dose of 0.0625-0.25 mg daily. This recommendation is based on the most recent and highest quality study available, which is the 2016 ESC guidelines for the management of atrial fibrillation 1. The guidelines suggest that the initial dose of digoxin can be given intravenously or orally, and the maintenance dose should be adjusted based on the patient's kidney function, age, and body weight. Some key points to consider when initiating digoxin therapy include:

• Assessing baseline serum potassium, magnesium, calcium, and renal function to minimize the risk of digoxin toxicity
• Monitoring digoxin levels, renal function, and electrolytes regularly to prevent toxicity
• Being aware of the potential side effects of digoxin, such as nausea, visual disturbances, and cardiac arrhythmias
• Using low doses (0.125 mg daily or every other day) initially in patients over 70 years of age or with impaired renal function, as suggested by the 2022 AHA/ACC/HFSA guideline for the management of heart failure 1. It's also important to note that the therapeutic serum digoxin level is typically 0.8-2.0 ng/mL, and higher doses are rarely required in the management of heart failure and are potentially detrimental, as shown in the 2022 AHA/ACC/HFSA guideline 1. Overall, the initial dose of digoxin for a patient with atrial fibrillation should be individualized based on the patient's specific needs and medical history, and regular monitoring is essential to minimize the risk of toxicity and ensure optimal treatment outcomes.

From the FDA Drug Label

A single initial dose of 500 to 750 mcg (0.5 to 0.75 mg) of digoxin tablets usually produces a detectable effect in 0.5 to 2 hours that becomes maximal in 2 to 6 hours. Peak digoxin body stores larger than the 8 to 12 mcg/kg required for most patients with heart failure and normal sinus rhythm have been used for control of ventricular rate in patients with atrial fibrillation Doses of digoxin used for the treatment of chronic atrial fibrillation should be titrated to the minimum dose that achieves the desired ventricular rate control without causing undesirable side effects.

The initial dose of digoxin for a patient with atrial fibrillation is 500 to 750 mcg (0.5 to 0.75 mg). The dose should be titrated to the minimum dose that achieves the desired ventricular rate control without causing undesirable side effects 2.

From the Research

Initial Dose of Digoxin for Atrial Fibrillation

• The initial dose of digoxin for a patient with atrial fibrillation is not explicitly stated in the provided studies as a specific value for the initial dose, but rather as a loading dose or an initial daily dose range.
• According to 3, the dosage of digoxin should be 0.125-0.25 mg daily in the majority of patients, and loading doses of digoxin are not necessary during initiation of therapy for patients with chronic heart failure.
• In the context of atrial fibrillation, 4 suggests that low dosages of digoxin appear to be effective in the treatment of heart failure due to systolic dysfunction and may reduce the incidence of digitalis toxicity in these patients.
• For patients with heart failure and atrial fibrillation with a rapid ventricular response, 3 recommends that high doses of digoxin (>0.25 mg daily) for the purpose of rate control are not recommended.

Considerations for Dosage

• The dosage should be adjusted based on the patient's age, renal function, and lean body mass 3.
• In elderly patients, a lower dose should be used, such as 0.125 mg daily 3, 4.
• The studies do not provide a specific initial dose for atrial fibrillation, but rather a daily dose range, suggesting that the initial dose may be the same as the daily maintenance dose.

Clinical Trials and Studies

• 5 describes a study where intravenous digoxin was used in combination with esmolol for the acute treatment of atrial fibrillation or flutter, with an initial dose of 0.25 mg or 0.5 mg of digoxin.
• 6 compares low-dose digoxin with bisoprolol for heart rate control in atrial fibrillation, with a mean dose of 161 μg/d of digoxin, but does not specify an initial dose.