What are the effective doses of digoxin (Digitalis) for Heart Failure (HF) and Atrial Fibrillation (AF)?

Effective Doses of Digoxin for Heart Failure and Atrial Fibrillation

For most patients with heart failure or atrial fibrillation, digoxin should be initiated at 0.125-0.25 mg daily, with lower doses (0.125 mg daily or every other day) for patients over 70 years, those with impaired renal function, or low lean body mass. 1

Dosing for Heart Failure (HF)

Initial Dosing

• Start with 0.125-0.25 mg daily for most adults with normal renal function 1, 2
• Use 0.125 mg daily or 0.0625 mg daily for patients >70 years, with impaired renal function, or low lean body mass 1
• Higher doses (0.375-0.50 mg daily) are rarely needed or recommended 1
• Loading doses are generally not required for chronic HF management 1, 2

Target Serum Concentration

• Aim for serum digoxin concentration between 0.5-0.9 ng/mL 1
• Concentrations >1.0 ng/mL have not shown superior outcomes and may increase mortality risk 1
• Toxicity is commonly associated with levels >2 ng/mL but can occur at lower levels with electrolyte abnormalities 1, 3

Patient Selection for HF

• Consider digoxin for patients with persistent symptoms despite guideline-directed medical therapy (GDMT) 1
• Most beneficial in patients with reduced ejection fraction (LVEF <40%) and NYHA class II-IV symptoms 1
• Digoxin reduces hospitalization for worsening HF but has no effect on mortality 1
• Not indicated as primary therapy for acute HF exacerbation 1, 3

Dosing for Atrial Fibrillation (AF)

Initial Dosing

• Same dosing principles as for HF: 0.125-0.25 mg daily for most adults 2
• Lower doses for elderly, renal impairment, or low body mass 2, 4
• For AF with rapid ventricular rate, digoxin is typically used in combination with beta-blockers 1, 5

Patient Selection for AF

• Most appropriate for patients with AF and concomitant HF 1, 5
• Consider for ventricular rate control in patients with sedentary lifestyle or who cannot tolerate beta-blockers 5, 4
• Beta-blockers are generally more effective for rate control, particularly during exercise 1, 5

Dose Adjustments and Monitoring

• Adjust dose based on renal function, age, and lean body weight 2
• For a 70 kg patient with creatinine clearance of 60 mL/min, recommended maintenance dose is 0.25 mg daily 2
• Monitor serum electrolytes (potassium, magnesium) and renal function regularly 1
• Steady-state serum concentrations typically achieved in 1-3 weeks depending on renal function 2
• Reduce dose when used with medications that increase digoxin levels (amiodarone, verapamil, quinidine, clarithromycin) 1

Contraindications and Cautions

• Avoid in patients with significant sinus or AV block without a permanent pacemaker 1
• Use cautiously with other drugs that affect AV nodal function 1
• Pre-existing pre-excitation syndromes (contraindicated) 1
• Caution in patients with hypokalemia, hypomagnesemia, or hypothyroidism 1, 3

Common Adverse Effects

• Cardiac arrhythmias (ectopic beats, heart block) 1
• Gastrointestinal symptoms (anorexia, nausea, vomiting) 1
• Neurological complaints (visual disturbances, confusion, disorientation) 1
• Signs of toxicity: confusion, nausea, anorexia, visual disturbances, arrhythmias 1, 3

The benefit of digoxin in contemporary HF management remains controversial, and GDMT should be optimized before considering the addition of digoxin 1, 6. Current research is evaluating whether lower doses (targeting 0.5-0.9 ng/mL) may provide better safety profiles while maintaining efficacy 6, 7.