1) Beta blocker 
<chemical> A beta-adrenergic antagonist that has been used in the emergency treatment of cardiac arrhythmias. ... Pharmacological action: adrenergic beta-antagonists, anti-arrhythmia agents, sympatholytics. ... Chemical name: Acetamide, N-(4-(2-hydroxy-3-((1-methylethyl)amino)propoxy)phenyl)- ... (12 Dec 1998) ...