Digoxin Specific Antibody

What it is and how it works

Ovine antigen-binding (Fab) fragments that bind digoxin and digitoxin with high affinity. They draw the glycoside away from Na+/K+-ATPase binding sites, reversing toxicity, and the Fab–glycoside complex is excreted by the kidneys.

Indications

Treatment of life-threatening or potentially life-threatening digoxin or digitoxin toxicity, including severe ventricular arrhythmias, progressive bradyarrhythmias, and hyperkalaemia due to cardiac glycoside overdose.

Dosage and administration (summary)

Dose is individualised according to the amount ingested or the steady-state serum digoxin concentration and body weight, using the manufacturer’s calculation tables; given by intravenous infusion, or as a bolus in cardiac arrest.

Contraindications

No absolute contraindications in life-threatening toxicity; caution in known allergy to sheep proteins or papain.

Warnings and precautions

Hypersensitivity reactions may occur, especially in patients allergic to ovine proteins or papain, or previously treated with ovine Fab. Reversal of toxicity can cause hypokalaemia, worsening heart failure and rapid ventricular response in atrial fibrillation; monitor potassium and ECG closely. Serum digoxin assays are unreliable after administration because total digoxin rises.

Pregnancy

Use if clearly needed in life-threatening toxicity; data are limited.

Storage and supply

Store refrigerated at 2–8 °C; do not freeze.

Source: reference summary prepared from the EU SmPC/EPAR, BNF and WHO Model Formulary. The approved product information in Iran governs.