How can I prepare my own bolus dose of amiodarone?

Preparing an Amiodarone Bolus Dose

For intravenous amiodarone bolus administration, dilute 150 mg of amiodarone in 100 mL of 5% dextrose in water (D5W) and infuse over 10 minutes for life-threatening arrhythmias, or over 1 hour for hemodynamically stable patients. 1, 2

Standard Bolus Preparation Protocol

Rapid Loading (Life-Threatening Situations)

• Dilute 150 mg amiodarone in 100 mL of D5W and administer over 10 minutes for cardiac arrest, hemodynamically unstable ventricular tachycardia, or immediately life-threatening arrhythmias 1, 2
• This rapid bolus may be repeated after 10-30 minutes if breakthrough arrhythmias persist 2
• The concentration will be approximately 1.5 mg/mL, which is safe for peripheral administration 2

Standard Loading (Stable Arrhythmias)

• Dilute 150 mg (or 5 mg/kg, approximately 300 mg for average adult) in 100 mL of D5W and infuse over 1 hour for hemodynamically stable atrial fibrillation or stable monomorphic ventricular tachycardia 2
• For the higher 300 mg dose, use 200 mL of D5W to maintain concentration ≤2 mg/mL 2

Critical Preparation Requirements

Diluent Selection

• Use only 5% dextrose in water (D5W) as the diluent—normal saline or lactated Ringer's solution will cause drug precipitation and loss of efficacy 2

Concentration Limits

• Keep concentration ≤2 mg/mL for peripheral IV administration; higher concentrations require central venous access due to high risk of phlebitis 2, 3
• Peripheral vein phlebitis occurs frequently with concentrations >2 mg/mL 2

Equipment Requirements

• Use a volumetric infusion pump rather than drop-counter devices, which can underdose by up to 30% 2
• Place an in-line filter in the infusion line 2
• Do not exceed an initial infusion rate of 30 mg/min 2

Post-Bolus Maintenance Infusion

After the initial bolus, continue with a two-phase maintenance regimen:

• Early maintenance: 1 mg/min for 6 hours (approximately 360 mg total) 1, 2
• Late maintenance: 0.5 mg/min for the subsequent 18 hours (approximately 540 mg total) 1, 2
• Total 24-hour dose: Approximately 1 gram, not to exceed 2.2 g in any 24-hour period 1, 2

Expected Onset of Action

• The antiarrhythmic effect typically becomes apparent 20-30 minutes after administration 2
• Most conversions to sinus rhythm occur after 6-8 hours of therapy and usually require a cumulative dose of at least 1 g 1, 2
• This delayed onset makes amiodarone less appropriate as a first-line agent unless the patient is clinically stable 2

Common Pitfalls to Avoid

Wrong Diluent

• Never use normal saline—this is the most common preparation error and results in drug precipitation 2

Concentration Too High

• Concentrations >2 mg/mL cause severe phlebitis in peripheral veins; 13% of patients develop superficial phlebitis even with proper dilution 3

Inadequate Monitoring

• Continuous ECG monitoring is mandatory during administration 2
• Monitor blood pressure closely—hypotension occurs in 16-26% of patients receiving IV amiodarone 1, 2
• Watch for bradycardia (occurs in 4.9% of patients) and AV block 2

Relative Contraindications

• Baseline heart rate <60 bpm: Use only if arrhythmia is immediately life-threatening and no alternatives exist 2
• Systolic blood pressure <100 mmHg: Higher risk for hemodynamic compromise 2
• Second- or third-degree heart block without pacemaker: Absolute contraindication 2

Drug Interaction Considerations

If the patient is on concurrent medications:

• Reduce digoxin dose by 50% immediately, as amiodarone doubles digoxin levels 4
• Reduce warfarin dose by 30-50% and check INR within 3-5 days 4
• Avoid grapefruit juice, which inhibits metabolism and increases plasma levels 2