Clinical Content
4 min read
February 3, 2023
4 min read
February 3, 2023
Digoxin Poisoning Management
J
Jimmy
PharmD
Clinical Content
2 min read
February 3, 2023
2 min read
February 3, 2023
Digoxin Poisoning Management
J
Jimmy
PharmD
Digoxin Poisoning Management
Pharmacy Friday Pearl – Pharmacy & Acute Care University
Introduction
- Digoxin treats atrial flutter, atrial fibrillation, and heart failure.
- Toxicity occurs when Na+/K+-ATPase inhibition raises intracellular Na+/Ca2+, triggering dysrhythmias.
- EKG red flags: PVCs, biphasic T waves, shortened QT interval, variable AV block.
- Therapeutic range 0.8 – 2.0 ng/mL; toxicity often begins > 2 ng/mL.
Digoxin Immune Fab (DigiFab / DigiBind)
| Parameter | Key Details |
|---|---|
| Dose |
1 vial = 40 mg (binds 0.5 mg digoxin). Unknown ingestion → 10-vial empiric dose. Alternative: vials = 2 × total body load (mg). Chronic unknown: adults 3 – 6 vials; children 1 – 2 vials. |
| Administration | IV infusion over 30 min (rapid bolus if arrest imminent). |
| Onset / Duration | Onset 20 – 90 min • Duration 15 – 20 h. |
| Adverse Effects | Orthostatic hypotension, ventricular tachycardia, hypokalemia. |
| Mechanism | Fab fragments swiftly bind circulating digoxin, neutralising toxicity. |
| Compatibility | Compatible only with 0.9 % sodium chloride. |
Clinical pearl: monitor serum K+ closely—intracellular shifts often trigger hypokalemia post-Fab.
Overview of Key Evidence
| Author / Year | Design (n) | Key Findings |
|---|---|---|
| Wei 2021 | Case series (121) | FAERS: DigiBind serious AEs 87 % vs DigiFab 63 %; hypotension, cardiac arrest, death most frequent. |
| Ward 2000 | Observational (16) | Both Fab products reduced free digoxin below assay limits; total digoxin ↑ ≈10-fold (binding confirmed). |
| Renard 1997 | Observational (16) | Fab clearance declined linearly with renal impairment & age; t½ 11 – 34 h; all patients recovered without AEs. |
| Antman 1990 | Open-label (150) | 90 % toxicity resolved/improved; median dose 5 vials (200 mg); maximum 40 vials. |
| Roberts 2016 | Systematic review | Fab therapy remains first-line; hyperkalemia & ventricular arrhythmias are key toxicity predictors. |
| Ujhelyi 1995 | PK review | Fab exhibits two-compartment kinetics; repeat dosing may be needed in large body-load poisonings. |
Clinical Conclusions
- Digoxin toxicity is life-threatening but rapidly reversible with Digoxin Immune Fab.
- If the ingested amount is unknown, administer an empiric 10-vial dose.
- Do not delay Fab therapy for age- or renal-based calculations.
Full Reference List
- Bismuth C, Gaultier M, Conso F, Efthymiou ML. Hyperkalemia in acute digitalis poisoning. Clin Toxicol. 1973;6(2):153-162.
- David MNV, Shetty M. Digoxin. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022.
- Lexicomp Online, Lexi-Drugs Online. Waltham, MA: UpToDate, Inc. January 2023.
- Antman EM et al. Treatment of life-threatening digitalis intoxication with digoxin-specific Fab fragments. Circulation. 1990;81(6):1744-1752.
- Renard C et al. Pharmacokinetics of digoxin-specific Fab: effects of renal function & age. Br J Clin Pharmacol. 1997;44(2):135-138.
- Roberts DM et al. Pharmacological treatment of cardiac glycoside poisoning. Br J Clin Pharmacol. 2016;81(3):488-495.
- Ujhelyi MR, Robert S. Pharmacokinetic aspects of digoxin-specific Fab therapy. Clin Pharmacokinet. 1995;28(6):483-493.
- Wei S et al. Adverse events with digoxin Immune Fab in FAERS 1986-2019. Drugs – Real World Outcomes. 2021;8:253-262.
- Ward SB et al. Pharmacokinetics & bioaffinity of DigiTAb vs Digibind. Ther Drug Monit. 2000;22(5):599-607.
Level Up Your Practice
Ready to advance your pharmacy career?
Join thousands of pharmacy professionals learning with PACU.
Level Up Your Practice
Ready to advance your pharmacy career?
Join thousands of pharmacy professionals learning with PACU.