From the Guidelines
Amiodarone Dosing
Amiodarone dosing typically initiates with a loading dose of 800-1600 mg per day for 1-3 weeks, followed by a maintenance dose of 200-400 mg per day 1.
- For life-threatening arrhythmias, an IV bolus of 150 mg over 10 minutes may be used, followed by 1 mg per minute for 6 hours, then 0.5 mg per minute for 18 hours, and finally reduced to oral dosing when possible 1.
- For ventricular arrhythmias, a loading dose of 800-1600 mg per day in divided doses is used until a total of 10 g has been given, then reduced to 200-400 mg per day 1.
- For atrial fibrillation, a loading dose of 600-800 mg per day in divided doses is used until a total of 10 g has been given, then reduced to 200 mg per day 1. Key considerations for amiodarone dosing include:
- Administration route and setting: IV for life-threatening arrhythmias, oral for ventricular and atrial fibrillation 1.
- Potential adverse effects: Hypotension, bradycardia, atrioventricular block, QT prolongation, torsades de pointes, gastrointestinal upset, constipation, and others 1, 2.
- Precautions and interactions: Sinus or AV conduction disease, inflammatory lung disease, hepatic dysfunction, hypothyroidism, hyperthyroidism, peripheral neuropathy, and interactions with other medications such as warfarin and digoxin 2.
From the FDA Drug Label
DOSAGE & ADMINISTRATION Amiodarone shows considerable interindividual variation in response. Thus, although a starting dose adequate to suppress life-threatening arrhythmias is needed, close monitoring with adjustment of dose as needed is essential The recommended starting dose of amiodarone HCl injection is about 1000 mg over the first 24 hours of therapy, delivered by the following infusion regimen: After the first 24 hours, the maintenance infusion rate of 0. 5 mg/min (720 mg/24 hours) should be continued utilizing a concentration of 1 to 6 mg/mL The first 24-hour dose may be individualized for each patient; however, in controlled clinical trials, mean daily doses above 2100 mg were associated with an increased risk of hypotension
The appropriate dosing for Amiodarone is:
- Initial dose: 1000 mg over the first 24 hours of therapy
- Maintenance dose: 0.5 mg/min (720 mg/24 hours)
- Maximum daily dose: should not exceed 2100 mg to minimize the risk of hypotension 3
From the Research
Amiodarone Dosing
The appropriate dosing for Amiodarone can be understood through the following points:
- A high dose oral amiodarone loading regimen of 50 mg/kg per day for 3 days, then 30 mg/kg per day for 2 days, followed by maintenance therapy of 300 to 400 mg twice daily, was found to be well tolerated in 15 of the 16 patients studied 4.
- This dosing regimen resulted in significant increases in ventricular tachycardia cycle length and right ventricular effective refractory period, starting on day 1 4.
- The study suggests that high dose oral loading of amiodarone can be safe and effective for patients with recurrent ventricular arrhythmias and decreased left ventricular function 4.
Comparison with Other Studies
- Other studies, such as the one on intravenous amrinone, do not provide direct evidence for Amiodarone dosing, as they focus on different medications and conditions 5.
- A study on risk factors for amiodarone-induced liver injury highlights the importance of monitoring liver function during amiodarone administration, but does not provide information on dosing 6.
Key Findings
- The high dose oral loading regimen of amiodarone was well tolerated and effective in reducing arrhythmias in patients with recurrent ventricular arrhythmias and decreased left ventricular function 4.
- Close monitoring of liver function is necessary when administering amiodarone to prevent drug-induced liver injury 6.