Digoxin IV Push Repetition
The 0.25-mg IV bolus of digoxin can be repeated up to a maximum total loading dose of 1.0 mg over 24 hours, with doses given at 6-8 hour intervals. 1
Specific Dosing Protocol
Initial and Repeat Dosing:
- Start with 0.25-0.5 mg IV bolus 1
- Repeat 0.25 mg IV bolus as needed 1
- Space doses at 6-8 hour intervals 1
- Do not exceed 1.0 mg total over 24 hours (equivalent to maximum loading dose of 8-12 mcg/kg) 1
This means you can give up to 4 doses of 0.25 mg each (or 2 doses of 0.5 mg) within 24 hours before reaching the maximum.
Critical Dosing Adjustments
Reduce the initial and repeat doses in these situations:
- Renal dysfunction: Use lower end of dosing range (0.125-0.25 mg) 1, 2
- Age >70 years: Use 0.125 mg doses 3
- Low lean body mass: Use 0.125 mg doses 3
- Concurrent amiodarone: Reduce digoxin dose by 30-50% 4, 3
- Creatinine clearance <60 mL/min: Consider loading doses of 6-10 mcg/kg (approximately 0.4-0.7 mg for 70 kg patient) 2
Monitoring Between Doses
Before giving each repeat dose, assess for:
- Heart rate response (target is rate control, not specific number) 1
- Signs of toxicity: nausea, vomiting, visual changes (yellow-green halos), new arrhythmias 1, 5
- Potassium level (hypokalemia increases toxicity risk) 3
- Renal function (digoxin is renally cleared) 1, 3
Absolute Contraindications to Repeat Dosing
Do not give additional doses if:
- AV block greater than first degree without pacemaker 1
- Wolff-Parkinson-White syndrome with atrial fibrillation/flutter 1
- Signs of digoxin toxicity appear 1
- Significant sinus or AV nodal dysfunction develops 3
Common Pitfall
The most dangerous error is giving repeat doses too quickly without allowing for distribution. Digoxin takes approximately 6 hours to fully distribute to tissues 6, 2. Measuring digoxin levels before 6 hours post-dose will overestimate the need for additional medication and increase toxicity risk 6, 2.