Which of the following medications is a beta blocker?

Carvedilol is classified as a beta blocker, which is a type of medication commonly used to manage various cardiovascular conditions, including hypertension and heart failure. Beta blockers work by blocking the effects of epinephrine (adrenaline) on beta-adrenergic receptors in the heart and blood vessels. This results in a decrease in heart rate, contractility, and overall cardiac output, which can help lower blood pressure and improve heart function.

In contrast, the other medications listed serve different therapeutic purposes. Amiodarone is an antiarrhythmic medication used to treat irregular heartbeats. Lisinopril is an angiotensin-converting enzyme (ACE) inhibitor utilized primarily for hypertension and heart failure management. Atorvastatin is a statin used to lower cholesterol levels and reduce the risk of cardiovascular disease. Therefore, among the options given, carvedilol is the only medication that fits the classification of a beta blocker.