Dronedarone Vs Amiodarone (Multaq Vs Amiodarone)

“Dronedarone Vs Amiodarone” compares two drugs commonly used to maintain normal sinus rhythm in patients with atrial fibrillation.

Atrial fibrillation is when electrical impulses bombard the AV node and the ventricles simultaneously resulting in rapid and irregular heart contractions.

Normally, one impulse travels via the AV node to the ventricles and this is followed by a cardiac contraction. However, in atrial fibrillation, multiple impulses travel at irregular intervals and so the ventricles contract rapidly and irregularly.

Various drugs are used to control the heart rate. These include:

• Beta-blockers
• Calcium channel blockers, and
• Digoxin

Anti-arrhythmic drugs are used to convert the rhythm into a normal sinus rhythm. These include:

• Quinidine
• Procainamide
• Flecainide
• Sotalol
• Amiodarone
• Dronedarone.

Here is a table summarizing the drugs used to treat atrial fibrillation:

Dronedarone (Multaq) Vs Amiodarone: Comparing the Pharmacokinetics:

To understand the difference between Dronedarone and Amiodarone, it is important to understand their pharmacokinetics.

A few important differences between Dronedarone Vs Amiodarone are:

• Dronedarone has a short half-life and so a shorter duration of action
• Dronedarone has an easy dosing schedule compared to Amiodarone
• Monitoring for thyroid function is not required when using Dronedarone Vs Amiodarone as Dronedarone (Multaq) does not contain iodine.

Other pharmacokinetic differences are highlighted in the table below:

Pros and Cons of Dronedarone Vs Amiodarone:

Both Dronedarone and amiodarone are considered to be equally effective. However, in patients with advanced decompensated heart failure, Amiodarone is considered to be a safer choice because of an increased risk of death from Dronderaone.

Contrary to patients with advanced structural heart disease, Dronedarone is more effective in maintaining sinus rhythm in patients with atrial fibrillation.

In addition, Dronedarone is much safer with fewer drug interactions and does not require monitoring of thyroid functions compared to Amiodarone.

The table below summarized the Pros and Cons of Dronedarone Vs Amiodarone:

The table above shows that although Dronedarone is considered less effective than amiodarone, it is safe, has fewer drug interactions, fewer side effects, easy dosing schedule, and does not interfere with the functioning of the thyroid gland.

These Pros and Cons are summarized in the table below:

Is Dronedarone really safe compared to Amiodarone?

Based on the information presented earlier, the pharmacokinetic parameters indicate that Dronedarone may be safer than Amiodarone.

However, the true safety of these drugs can be determined through clinical trials involving human subjects.

In a published study, the author summarized the following findings [Ref]:

The table above shows the comparison of the outcomes between Dronedarone and Amiodarone treatments.

For every 1,000 patients treated with Dronedarone instead of Amiodarone, there would be approximately 228 more recurrences of atrial fibrillation (AF), but 62 fewer adverse events requiring discontinuation of the drug.

There was no significant difference in all-cause mortality between the two drugs.

The incidence of thyroid toxicity, symptomatic bradyarrhythmias, and hepatotoxicity were comparable between Dronedarone and placebo, while the incidence of these adverse effects was higher with Amiodarone than with placebo.

In addition, the FDA has issued a serious warning, known as a “Black Box Warning,” for the use of MULTAQ in certain situations. These include [Ref]:

• Patients with NYHA Class IV heart failure, where the risk of death doubles.
• Patients with symptomatic heart failure who have recently been hospitalized for heart failure, where the risk of death doubles.
• Patients with permanent atrial fibrillation who are unable to convert to normal sinus rhythm, where the risk of stroke, hospitalization, and death doubles.

Efficacy of Dronedarone Vs Amiodarone:

Dronedarone is less effective than amiodarone, especially in patients with structural heart disease and heart failure.

In atrial fibrillation, it is equally effective as amiodarone and other anti-arrhythmic drugs. It has been shown to lower the risk of death and hospitalizations in patients with atrial flutter and atrial fibrillation.

Additionally, dronedarone may have the benefit of lowering blood pressure and reducing ischemic events. However, its main advantages, which the manufacturer emphasizes, are that:

• it is safer than amiodarone,
• has fewer drug interactions, and
• comes with an easy dosing schedule.

Cost of Dronedarone Vs Amiodarone:

Amiodarone is much cheaper than Dronedarone (Multaq). The average monthly cost of Amiodarone is roughly USD 60$.

Compared to Amiodarone, Dronedarone (Multaq) is about 10 times more expensive. The monthly supply of Dronedarone (Multaq) costs around USD 800$ +/-100$.