Esmolol Hydrochloride is a beta-adrenergic blocker indicated for short-term treatment of:

• Control of ventricular rate in supraventricular tachycardia, including atrial fibrillation and atrial flutter, and management of heart rate in noncompensatory sinus tachycardia.
• Control of perioperative tachycardia and hypertension.

Esmolol Hydrochloride is a beta-1 selective (cardioselective) adrenergic receptor blocking agent with a rapid onset and a very short duration of action. At therapeutic doses, it has no significant intrinsic sympathomimetic or membrane-stabilizing activity. The elimination half-life following intravenous infusion is approximately 9 minutes. Esmolol primarily blocks beta-1 receptors located in cardiac muscle; however, this selectivity is not absolute. At higher doses, it may also inhibit beta-2 receptors found mainly in bronchial and vascular smooth muscle.

Administer intravenously. Adjust (titrate) the dose based on ventricular rate or blood pressure at intervals of ≥4 minutes.

Supraventricular tachycardia (SVT) or noncompensatory sinus tachycardia:

• Optional loading dose: 500 mcg/kg infused over 1 minute
• Followed by 50 mcg/kg/min for the next 4 minutes
• Adjust dose as required up to a maximum of 200 mcg/kg/min
• Additional loading doses may be given if necessary

Perioperative tachycardia and hypertension:

• Loading dose: 500 mcg/kg over 1 minute for gradual control (or 1 mg/kg over 30 seconds for rapid control)
• Then 50 mcg/kg/min for gradual control (or 150 mcg/kg/min for rapid control), titrated up to a maximum of 200 mcg/kg/min (tachycardia) or 300 mcg/kg/min (hypertension)

• Digitalis glycosides: Increased risk of bradycardia
• Anticholinesterases: May prolong neuromuscular blockade
• Antihypertensive agents: Risk of rebound hypertension
• Sympathomimetic drugs: Dose adjustment may be required
• Vasoconstrictive and positive inotropic agents: Concomitant use should be avoided

• Severe sinus bradycardia
• Heart block greater than first degree
• Sick sinus syndrome
• Decompensated heart failure
• Cardiogenic shock
• Concomitant use of IV cardiodepressant calcium-channel blockers (e.g., verapamil) in close timing with esmolol hydrochloride
• Pulmonary hypertension
• Known hypersensitivity to esmolol

The most common adverse reactions (incidence >10%) include symptomatic hypotension (such as excessive sweating and dizziness) as well as asymptomatic hypotension.

Pregnancy Category C. Esmolol hydrochloride has been associated with increased fetal resorption in animal studies (rabbits) at doses approximately 8 times higher than the maximum recommended human maintenance dose (300 mcg/kg/min), with minimal maternal toxicity. There are no adequate and well-controlled studies in pregnant women. Therefore, esmolol hydrochloride should be used during pregnancy only if the expected benefit outweighs the potential risk to the fetus. It is not known whether this drug is excreted in human breast milk. Since many drugs are excreted in breast milk and there is a possibility of serious adverse effects in nursing infants, a decision should be made either to discontinue breastfeeding or to discontinue the drug, considering the importance of the medication to the mother.

• Risk of hypotension, bradycardia, and cardiac failure: Reduce dose or discontinue if necessary
• May worsen reactive airway diseases
• In diabetes mellitus: Enhances the effect of hypoglycemic agents and may mask signs of hypoglycemia (e.g., tachycardia)
• Risk of unopposed alpha-adrenergic activity and severe hypertension in untreated pheochromocytoma
• Risk of myocardial ischemia if abruptly discontinued in patients with coronary artery disease

Pediatric Use: Safety and effectiveness of Esmolol Hydrochloride in pediatric patients have not been established.

Geriatric Use: Clinical studies did not include enough patients aged 65 years and above to determine whether they respond differently compared to younger individuals.

Hepatic Impairment: No special precautions are required, as Esmolol Hydrochloride is metabolized by red blood cell esterases.

Renal Impairment: No dosage adjustment is required in patients with renal impairment receiving maintenance infusion of esmolol 150 mcg/kg for up to 4 hours.

Anti-adrenergic agent (Beta-blockers)

Store below 25°C, protected from light and moisture. Keep out of reach of children.