What is the second medication used in the treatment of ventricular fibrillation?

Amiodarone is the second medication commonly utilized in the treatment of ventricular fibrillation (VF) during advanced cardiac life support (ACLS). When a patient presents with VF that is resistant to initial defibrillation attempts, the administration of amiodarone is indicated due to its antiarrhythmic properties. It works by prolonging the refractory period in the myocardial tissue, which stabilizes the cardiac rhythm and allows for effective electrical activity to be restored.

Epinephrine is often the first-line medication administered during cardiac arrest, typically used in conjunction with defibrillation efforts. Lidocaine, while also an antiarrhythmic, is less commonly used in the current guidelines for VF treatment. Adenosine is primarily indicated for specific supraventricular tachycardias and has no role in treating ventricular fibrillation. Thus, amiodarone is established as the second agent of choice after the initial defibrillation attempts and epinephrine administration in the ACLS protocol for managing VF.