What are the intravenous (IV) forms of beta blockers?

From the Guidelines

Intravenous beta blockers, such as metoprolol, esmolol, and propranolol, are recommended for use in emergency situations, with careful monitoring of heart rate, blood pressure, and cardiac function, due to their potential to cause bradycardia, hypotension, and heart failure exacerbation 1.

Key Points

• The most commonly used IV beta blockers include metoprolol, esmolol, propranolol, labetalol, and atenolol.
• These medications are primarily used in emergency situations such as acute coronary syndromes, hypertensive emergencies, tachyarrhythmias, and aortic dissection.
• IV beta blockers work by competitively blocking catecholamine binding at beta-adrenergic receptors, reducing heart rate, contractility, and blood pressure.
• Esmolol is particularly useful in critical care settings due to its ultra-short half-life (9 minutes), allowing for quick titration and reversal of effects if adverse reactions occur.

Dosage and Administration

• Metoprolol: initial dose 5 mg IV over 2-5 minutes, may repeat twice at 5-minute intervals for a total of 15 mg.
• Esmolol: loading dose 500 mcg/kg over 1 minute, followed by 50-300 mcg/kg/min infusion.
• Propranolol: 1-3 mg IV at 1 mg/minute, may repeat after 2 minutes.
• Labetalol: 10-20 mg IV over 2 minutes, followed by 20-80 mg every 10 minutes or continuous infusion of 2 mg/min.
• Atenolol: 5 mg IV over 5 minutes, may repeat once after 10 minutes.

Important Considerations

• Careful monitoring of heart rate, blood pressure, and cardiac function is essential during administration.
• Contraindications include marked first-degree AV block, second- or third-degree AV block, asthma, severe LV dysfunction or HF, and high risk for shock.
• Patients with significant chronic obstructive pulmonary disease should be given beta blockers cautiously, with initial selection favoring a short-acting beta-1–specific drug such as metoprolol or esmolol.

From the FDA Drug Label

Esmolol hydrochloride injection, for intravenous administration, is a beta adrenergic receptor blocker with a very short duration of action Metoprolol Tartrate Injection, USP, is a selective beta 1-adrenoreceptor blocking agent, available in 5 mL vials for intravenous administration.

The IV forms of beta blockers mentioned are:

• Esmolol (IV) 2
• Metoprolol (IV) 3

From the Research

IV Forms of Beta Blockers

• Esmolol is a unique cardioselective, intravenous, ultra-short acting, beta-adrenergic blocking agent 4
• It has a 9-minute half-life with rapid clinical onset and offset of action and the ability to titrate the drug to changing circumstances 4
• Esmolol is effective in specific clinical settings, such as unstable angina, myocardial infarction, atrial fibrillation or flutter, and supraventricular tachycardia 4
• It is also effective in the emergency management of hypertension, tachycardia, or arrhythmia in critical care units, emergency rooms, and surgery 4

Dosage and Administration

• Esmolol is infused intravenously in doses ranging from 25-300 micrograms/kg/min, along with a loading dose or bolus 4
• The dosage and administration must be individualized, and careful titration of the esmolol infusion and monitoring of therapeutic and safety parameters are necessary 5
• The most frequently reported adverse effect associated with esmolol infusion is hypotension, which can be corrected by down-titrating or discontinuing the infusion 4

Clinical Indications

• Esmolol is indicated for the treatment of supraventricular tachycardia, perioperative tachycardia and hypertension, and myocardial ischemic conditions such as acute myocardial infarction and unstable angina 5, 6
• It is also effective in attenuating the tachycardia and hypertension seen during the intraoperative period 7
• Esmolol is ideal as sole-agent therapy for the treatment of moderate postoperative hypertension associated with a hyperdynamic state 7

Safety and Efficacy

• Esmolol has been shown to be safe and effective in reducing the ventricular rate in patients with supraventricular tachyarrhythmias, and in reducing the heart rate in patients with acute myocardial infarction and/or unstable angina 7, 8
• The short duration of action and titratability of esmolol make it an ideal drug for use in patients in whom the clinical need for beta blockade is limited in duration 7
• The adverse effect profile of esmolol is similar to that of other beta blockers, with asymptomatic hypotension being the most commonly observed adverse effect 6