What is the recommended protocol for administering amiodarone (antiarrhythmic medication)?

Amiodarone Administration Protocol

The recommended protocol for administering amiodarone includes a loading dose of 150 mg IV over 10 minutes (may be repeated if necessary), followed by 1 mg/min for 6 hours, then 0.5 mg/min for 18 hours, with total dose not exceeding 2.2 g over 24 hours. 1

Intravenous Administration Protocol

Life-Threatening Arrhythmias (Acute Treatment)

• Initial bolus: 150 mg IV over 10 minutes 1
• If necessary, bolus may be repeated in 10-30 minutes 1, 2
• Early maintenance: 1 mg/min infusion for 6 hours (360 mg) 1
• Later maintenance: 0.5 mg/min infusion for 18 hours (540 mg) 1
• Total dose over 24 hours should not exceed 2.2 g 1

Administration Considerations

• Use volumetric infusion pump for administration 2
• Whenever possible, administer through a central venous catheter dedicated to that purpose 2
• Use an in-line filter during administration 2
• For infusions longer than 1 hour, do not exceed concentrations of 2 mg/mL unless using a central venous catheter 2
• Infusions exceeding 2 hours must be administered in glass or polyolefin bottles containing D5W 2
• Monitor for hypotension, bradycardia, and atrioventricular block during infusion 1

Oral Administration Protocol

Ventricular Arrhythmias

• Loading dose: 800-1,600 mg/day in divided doses until a total of 10 g has been given 1
• Maintenance dose: 200-400 mg/day 1

Atrial Fibrillation

• Loading dose: 600-800 mg/day in divided doses until a total of 10 g has been given 1
• Maintenance dose: 200 mg/day 1

Transition from IV to Oral Therapy

• For patients who received IV amiodarone for less than one week: 800-1,600 mg oral amiodarone per day 1
• For patients who received IV amiodarone for one to three weeks: 600-800 mg oral amiodarone per day 1
• For patients who received IV amiodarone for more than three weeks: 400 mg oral amiodarone per day 1

Monitoring Requirements

During IV Administration

• Continuous cardiac monitoring 1, 2
• Regular blood pressure monitoring 1, 2
• Monitor for hypotension, bradycardia, and AV block 1

Long-term Monitoring

• Baseline and periodic pulmonary function tests (most serious potential adverse effect is pulmonary toxicity) 1
• Thyroid function tests 1
• Liver function tests 1
• Ophthalmologic examinations 1
• ECG monitoring 1

Common Pitfalls and Precautions

• Avoid rapid infusion rates exceeding recommended protocols as they can lead to hepatocellular necrosis and acute renal failure 2
• Amiodarone has numerous drug interactions due to its effects on multiple ion channels and receptors 1
• Amiodarone has an extremely long half-life (IV: 9-36 days; Oral: 26-107 days), which can lead to accumulation and delayed onset of adverse effects 1
• Avoid grapefruit juice during treatment with oral amiodarone as it inhibits metabolism and increases plasma levels 2
• Be cautious with concomitant use of other QT-prolonging medications 1
• Amiodarone adsorbs to polyvinyl chloride (PVC) tubing, which may affect dosing accuracy 2

Special Considerations

• In patients with moderate or severe left ventricular failure, use with caution as it may cause negative inotropic effects 1
• Amiodarone may be particularly beneficial in patients with rapid ventricular rates or impaired renal function 1
• The frequency of most adverse effects is related to total amiodarone exposure (dosage and duration of treatment), so use the lowest effective dose 1
• For breakthrough episodes of ventricular fibrillation or hemodynamically unstable ventricular tachycardia, use 150 mg supplemental infusions over 10 minutes 2