Risk Factors for Digoxin Toxicity Should Raise the Index of Clinical Suspicion
- Patients undergoing digoxin therapy who exhibit risk factors for digoxin toxicity should be closely monitored so that any signs of poisoning are identified early to ensure timely treatment.1
Risk factors for potentially life-threatening digoxin toxicity
Decreased Renal Function1,4
Renal impairment can lead to increased digoxin levels, as digoxin is primarily eliminated by the kidneys1-4
Multiple Concomitant Medications4
Many medications can cause pharmacokinetic and pharmacodynamic interactions with digoxin or a decrease in renal function4
Advanced Age and Medical Illness3-6
Older patients are more likely to have decreased renal function and to be taking potentially interacting concomitant medications3-5; advanced heart failure is also associated with decreased renal function6
Electrolyte Imbalance1,2
Certain electrolyte imbalances (e.g., hypokalemia, hypercalcemia, hypomagnesemia) can increase sensitivity to digoxin effects1,2*
Particularly with loop diuretic use in chronic digoxin toxicity, hypokalemia may increase sensitivity to digoxin effects2
*In patients with toxicity from acute ingestion, hyperkalemia is associated with high mortality2
Fluid Status1,4
Fluid loss or poor fluid intake can lead to electrolyte imbalance1,4
Any ONE
should raise clinical suspicion for
POTENTIALLY LIFE-THREATENING DIGOXIN TOXICITY
Many Commonly Prescribed Drugs Have Interactions With Digoxin
Common medications that interact with digoxin2† | |||
---|---|---|---|
Antiarrhythmics | Amiodarone, propafenone, quinidine | Calcium channel blockers | Nifedipine, diltiazem, verapamil |
Antibiotics | Macrolides, tetracyclines | Diuretics | Spironolactone |
Antiviral | Ritonavir | Immunosuppressants | Cyclosporine |
Antidiarrheal agents | Diphenoxylate | NSAIDs | Diclofenac, indomethacin |
Antifungals | Azole antifungals | Benzodiazepines | Alprazolam |
Antimuscarinic agent | Propantheline | Beta blockers | Carvedilol |
ACEI/ARBs | Captopril, telmisartan | PPI | Lansoprazole, omeprazole, esomeprazole, rabeprazole |
Antidiabetic agents | Metformin | ||
Antiarrhythmics | Amiodarone, propafenone, quinidine | ||
Antibiotics | Macrolides, tetracyclines | ||
Antiviral | Ritonavir | ||
Antidiarrheal agents | Diphenoxylate | ||
Antifungals | Azole antifungals | ||
Antimuscarinic agent | Propantheline | ||
ACEI/ARBs | Captopril, telmisartan | ||
Antidiabetic agents | Metformin | ||
Calcium channel blockers | Nifedipine, diltiazem, verapamil | ||
Diuretics | Spironolactone | ||
Immunosuppressants | Cyclosporine | ||
NSAIDs | Diclofenac, indomethacin | ||
Benzodiazepines | Alprazolam | ||
Beta blockers | Carvedilol | ||
PPI | Lansoprazole, omeprazole, esomeprazole, rabeprazole |
58% of digoxin toxicity cases had the patient start a new medication prior to their ED admission7,‡
†Not an exhaustive list of drug interactions with digoxin.
‡Results from a retrospective chart review from 2019 to 2022 on all patients admitted with a toxic serum digoxin level where the established therapeutic range for digoxin was 0.8-2.0 ng/ml.7
ACEI, angiotensin-converting enzyme inhibitor; ARB, angiotensin II receptor blocker; ED, emergency department; NSAID, nonsteroidal anti-inflammatory drug; PPI, proton pump inhibitor.