Atenolol (English: Atenolol) is a selective β1 adrenergic receptor (English: Beta-1 receptor) antagonist, a beta blocker, used to treat cardiovascular disease. In 1976, Atenolol was developed to replace Propranolol as a drug to treat hypertension, reducing the activity of the heart. However, unlike propranolol, Atenolol does not pass through the blood-brain barrier, thereby avoiding various side effects on the central nervous system.