What is the dosing for Amiodarone (amiodarone) in ventricular tachycardia (Vtach)?

From the Guidelines

For ventricular tachycardia (VTach), amiodarone should be administered as a 150 mg IV dose over 10 minutes, with repeat doses as needed if VT recurs, followed by a maintenance infusion of 1 mg/min for the first 6 hours. This dosing regimen is based on the most recent and highest quality study available, which prioritizes minimizing morbidity, mortality, and improving quality of life 1. The use of amiodarone in VTach is supported by its effectiveness in blocking multiple ion channels and its alpha and beta-adrenergic blocking properties, making it a valuable treatment option for various arrhythmias.

Key Considerations

• Amiodarone dosing for VTach should be initiated with a 150 mg IV dose over 10 minutes, with the possibility of repeat doses if necessary 1.
• A maintenance infusion of 1 mg/min for the first 6 hours is recommended after the initial dose 1.
• It is crucial to monitor patients for potential side effects, including QT prolongation, organ toxicities (thyroid, liver, lung), and drug interactions 1.
• Dose adjustments may be necessary for patients with hepatic dysfunction, considering amiodarone's long half-life (15-142 days) and its impact on both efficacy and side effects 1.

Comparison with Other Studies

While other studies suggest varying dosing regimens and comparisons with other antiarrhythmic drugs like lidocaine and procainamide 1, the most recent and highest quality evidence supports the use of amiodarone as described, prioritizing its efficacy and safety profile in the management of VTach.

From the FDA Drug Label

The recommended starting dose of amiodarone is about 1000 mg over the first 24 hours of therapy, delivered by the following infusion regimen: In the event of breakthrough episodes of VF or hemodynamically unstable VT, use 150 mg supplemental infusions of amiodarone (mixed in 100 mL of D5W and infused over 10 minutes to minimize the potential for hypotension)

The dosing for Vtach with amiodarone is as follows:

• Initial dose: 1000 mg over the first 24 hours
• Supplemental dose for breakthrough episodes: 150 mg infused over 10 minutes 2
• The dose may be adjusted based on the patient's response to the medication, with a maintenance infusion rate of 0.5 mg/min (720 mg per 24 hours) 2

From the Research

Amiodarone Dosing for Ventricular Tachycardia (Vtach)

• The dosing of amiodarone for Vtach can vary, with different studies suggesting different regimens.
• A study from 1993 3 compared conventional and high-dose loading regimens of amiodarone in patients with sustained ventricular tachycardia, finding that the therapeutic and electrophysiologic effects of conventional and high-dose loading regimens of amiodarone do not differ significantly after 3 or 10 days of therapy.
• Another study from 1983 4 used a chronic treatment dose of 800-1000 mg per day, with some patients also receiving a previously ineffective conventional agent.
• A 1985 study 5 compared oral loading alone with combined intravenous and oral loading, finding that the time to optimal ventricular arrhythmia control was shorter with the combined regimen.
• More recent studies, such as one from 2010 6, have highlighted the efficacy and safety of amiodarone in terminating and preventing ventricular arrhythmia, while also noting the importance of careful patient surveillance due to potential adverse effects.
• A 2002 study 7 compared intravenous amiodarone with intravenous lidocaine for the treatment of incessant ventricular tachycardia, finding that amiodarone was more effective in terminating VT and improving 24-hour survival.

Key Findings

• Amiodarone is an effective treatment for ventricular tachycardia, with various dosing regimens used in different studies.
• The choice of dosing regimen may depend on the specific clinical context and patient characteristics.
• Careful patient surveillance is necessary due to the potential for adverse effects with amiodarone therapy, as noted in studies such as 4 and 6.
• Amiodarone has been shown to be more effective than other treatments, such as lidocaine, in certain situations, as demonstrated in the 2002 study 7.