Esmolol: a novel cardioselective, titratable, intravenous beta-blocker with ultrashort half-life.

Esmolol is an ultrashort-acting, cardioselective, intravenous beta-blocker with an elimination half-life of about nine minutes. After administration of a loading dose, its full therapeutic effect is evident within five minutes. Its efficacy in treating supraventricular arrhythmias is equal to that of propranolol, but unlike propranolol, the action of esmolol is titratable and is largely reversed within 10 to 30 minutes after stopping its administration. Esmolol is also effective in attenuating life-threatening perioperative tachycardia and hypertension caused by adrenergic stimulation in high-risk patients.