From the Guidelines
The treatment for digoxin toxicity is primarily focused on administering digoxin-specific antibody fragments (digoxin-Fab) for severe cases, as recommended by the 2023 American Heart Association guidelines 1.
Key Recommendations
- Administration of digoxin-Fab is recommended for digoxin or digitoxin poisoning, with a Class of Recommendation (COR) of 1 and a Level of Evidence (LOE) of B-NR 1.
- The dose of digoxin-Fab depends on the severity of the toxicity and the amount of digoxin ingested or the serum digoxin level.
- Supportive care includes correcting electrolyte abnormalities, particularly potassium, and treating arrhythmias with medications such as atropine, lidocaine, or phenytoin.
Management of Specific Conditions
- Bradydysrhythmias caused by digoxin and other cardiac glycoside poisoning may be treated with atropine or temporary pacing 1.
- Ventricular dysrhythmias can be treated with lidocaine, phenytoin, or bretylium until digoxin-Fab can be administered 1.
- Hyperkalemia is a marker of severity in acute cardiac glycoside poisoning and may require empirical administration of antidigoxin Fab 1.
Important Considerations
- Hemodialysis, hemofiltration, hemoperfusion, or plasmapheresis are not recommended for treating digoxin poisoning due to its large volume of distribution and the ineffectiveness of these methods in removing the drug 1.
- Continuous cardiac monitoring is essential throughout treatment to promptly identify and manage any life-threatening arrhythmias or conduction abnormalities.
From the FDA Drug Label
OVERDOSAGE Digoxin should be temporarily discontinued until the adverse reaction resolves. Every effort should also be made to correct factors that may contribute to the adverse reaction (such as electrolyte disturbances or concurrent medications). Treatment of Adverse Reactions Produced by Overdosage: Withdrawal of digoxin may be all that is required to treat the adverse reaction. However, when the primary manifestation of digoxin overdosage is a cardiac arrhythmia, additional therapy may be needed If the rhythm disturbance is a symptomatic bradyarrhythmia or heart block, consideration should be given to the reversal of toxicity with DIGIBIND® [Digoxin Immune Fab (Ovine)] (see Massive Digitalis Overdosage subsection), the use of atropine, or the insertion of a temporary cardiac pacemaker If the rhythm disturbance is a ventricular arrhythmia, consideration should be given to the correction of electrolyte disorders, particularly if hypokalemia (see Administration of Potassium subsection) or hypomagnesemia is present DIGIBIND is a specific antidote for digoxin and may be used to reverse potentially life-threatening ventricular arrhythmias due to digoxin overdosage.
The treatment for digoxin toxicity includes:
- Temporary discontinuation of digoxin until the adverse reaction resolves
- Correction of contributing factors such as electrolyte disturbances or concurrent medications
- Withdrawal of digoxin may be sufficient to treat the adverse reaction
- Additional therapy may be needed for cardiac arrhythmias, including:
- DIGIBIND (Digoxin Immune Fab) for reversal of toxicity
- Atropine for symptomatic bradyarrhythmia or heart block
- Temporary cardiac pacemaker for symptomatic bradyarrhythmia or heart block
- Correction of electrolyte disorders for ventricular arrhythmias, particularly hypokalemia or hypomagnesemia
- Administration of potassium orally or intravenously, with caution and monitoring for potassium toxicity 2
From the Research
Treatment for Digoxin Toxicity
The treatment for digoxin toxicity typically involves supportive care and the administration of digoxin-specific antibody fragments (digoxin-Fab) 3, 4, 5, 6.
- Digoxin-Fab is a safe and effective treatment for acute and chronic digoxin poisoning, with a response rate of 80-90% in acute poisonings and 50% in chronic poisonings 3.
- The dosage of digoxin-Fab depends on the severity of the toxicity and the patient's renal function, with a recommended dose of 80 mg bolus in acute poisoning, repeated as necessary, and 40 mg (1 vial) in chronic poisoning, repeated after 60 min if symptoms persist 3.
- Digoxin-Fab has a mean plasma half-life of 19-30 h and a volume of distribution of 0.4 L/kg, and its half-life is prolonged in renal failure to over 100 h 3.
- In cases of severe renal impairment, plasma exchange (PEX) may be considered to remove digoxin-DSA complexes and facilitate recovery 7.
Indications for Digoxin-Fab
The indications for digoxin-Fab include:
- Life-threatening tachy-bradyarrhythmias
- Hyperkalaemia (> 6 mmol/L)
- Haemodynamic instability with an elevated digoxin concentration (> 2 μg/L or 2.6 nmol/L) 3, 4, 5
- Severe digoxin toxicity with acute kidney injury, where plasma exchange (PEX) may be considered 7
Safety and Efficacy of Digoxin-Fab
- Digoxin-Fab is generally safe, with adverse events such as exacerbation of heart failure, increased ventricular rate, and hypokalaemia being uncommon (< 10%) 3.
- The efficacy of digoxin-Fab has been demonstrated in several studies, with a significant reduction in mortality and morbidity in patients with digoxin toxicity 3, 6.