What type of medication is amiodarone (Cordarone)?

Amiodarone is classified as a potassium channel blocker. It primarily functions by inhibiting potassium channels in cardiac cells, which helps to prolong the action potential and refractory period in the heart. This mechanism is crucial for controlling the heart rhythm, particularly in conditions such as ventricular tachycardia and atrial fibrillation. By blocking potassium channels, amiodarone effectively stabilizes the heart's electrical activity, making it a key medication in the management of serious arrhythmias.

The other classifications listed do not accurately describe the pharmacological action of amiodarone. Calcium channel blockers, for instance, primarily target calcium channels to decrease heart contractility and dilate blood vessels. Beta-blockers mainly block the effects of adrenaline on beta-adrenergic receptors, leading to reduced heart rate and contractility. ACE inhibitors work by inhibiting the angiotensin-converting enzyme to lower blood pressure through vasodilation and decreased fluid retention. Thus, understanding the specific pharmacological mechanism of amiodarone reinforces its classification as a potassium channel blocker.