Which medication is classified as a beta-blocker?

Atenolol is classified as a beta-blocker, a type of medication that primarily affects the cardiovascular system by blocking the action of certain neurotransmitters such as epinephrine on beta-adrenergic receptors. This action results in a decrease in heart rate, reduced force of contraction, and a lower blood pressure, making beta-blockers useful for treating conditions such as hypertension, heart rhythm disorders, and heart failure. Additionally, beta-blockers can be beneficial in reducing anxiety and the frequency of migraines.

The other medications listed have different classifications and purposes. Metformin is an oral hypoglycemic agent primarily used in the management of type 2 diabetes, simvastatin is a statin used to lower cholesterol levels and reduce cardiovascular risk, and lisinopril is an ACE inhibitor typically prescribed for hypertension and heart failure management. Each of these medications has unique mechanisms of action that differ significantly from that of beta-blockers.