2 DOSAGE AND ADMINISTRATION 2.1 Dosing for the Treatment of Supraventricular Tachycardia or Noncompensatory Sinus Tachycardia Esmolol hydrochloride injection is administered by continuous intravenous infusion with or without a loading dose. Additional loading doses and/or titration of the maintenance infusion (step-wise dosing) may be necessary based on desired ventricular response. In the absence of loading doses, continuous infusion of a single concentration of esmolol reaches pharmacokinetic and pharmacodynamic steady-state in about 30 minutes. The effective maintenance dose for continuous and step-wise dosing is 50 to 200 mcg per kg per minute, although doses as low as 25 mcg per kg per minute have been adequate. Dosages greater than 200 mcg per kg per minute provide little added heart-rate lowering effect, and the rate of adverse reactions increases. Maintenance infusions may be continued for up to 48 hours. 2.2 Intraoperative and Postoperative Tachycardia and Hypertension In this setting it is not always advisable to slowly titrate to a therapeutic effect. Therefore two dosing options are presented: immediate control and gradual control. Immediate Control Administer 1 mg per kg as a bolus dose over 30 seconds followed by an infusion of 150 mcg per kg per min if necessary. Adjust the infusion rate as required to maintain desired heart rate and blood pressure. Refer to Maximum Recommended Doses below. Gradual Control Administer 500 mcg per kg as a bolus dose over 1 minute followed by a maintenance infusion of 50 mcg per kg per min for 4 minutes. Depending on the response obtained, continue dosing as outlined for supraventricular tachycardia (refer to Table 1). Refer to Maximum Recommended Doses below. Maximum Recommended Doses For the treatment of tachycardia, maintenance infusion dosages greater than 200 mcg per kg per min are not recommended; dosages greater than 200 mcg per kg per min provide little additional heart rate-lowering effect, and the rate of adverse reactions increases. For the treatment of hypertension, higher maintenance infusion dosages (250 to 300 mcg per kg per min) may be required. The safety of doses above 300 mcg per kg per minute has not been studied. 2.3 Transition from Esmolol Hydrochloride Injection Therapy to Alternative Drugs After patients achieve adequate control of the heart rate and a stable clinical status, transition to alternative antiarrhythmic drugs may be accomplished. When transitioning from esmolol hydrochloride injection to alternative drugs, the physician should carefully consider the labeling instructions of the alternative drug selected and reduce the dosage of esmolol hydrochloride injection as follows: 1. Thirty minutes following the first dose of the alternative drug, reduce the esmolol hydrochloride infusion rate by one-half (50%). 2. After administration of the second dose of the alternative drug, monitor the patient's response, and, if satisfactory control is maintained for the first hour, discontinue the esmolol hydrochloride infusion. 2.4 Directions for Use Esmolol hydrochloride injection is available in a single dose vial. Esmolol hydrochloride injection is not compatible with Sodium Bicarbonate (5%) solution (limited stability) or furosemide (precipitation). Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit. Single-Dose Vial The Single-Dose Vial may be used to administer a loading dosage by hand-held syringe while the maintenance infusion is being prepared. Compatibility with Commonly Used Intravenous Fluids Esmolol hydrochloride injection was tested for compatibility with ten commonly used intravenous fluids at a final concentration of 10 mg Esmolol Hydrochloride per mL. Esmolol hydrochloride injection was found to be compatible with the following solutions and was stable for at least 24 hours at controlled room temperature or under refrigeration: Dextrose (5%) Injection, USP Dextrose (5%) in Lactated Ringer’s Injection Dextrose (5%) in Ringer’s Injection Dextrose (5%) and Sodium Chloride (0.45%) Injection, USP Dextrose (5%) and Sodium Chloride (0.9%) Injection, USP Lactated Ringer’s Injection, USP Potassium Chloride (40 mEq/liter) in Dextrose (5%) Injection, USP Sodium Chloride (0.45%) Injection, USP Sodium Chloride (0.9%) Injection, USP Administer intravenously (2.1, 2.2) Titrate using ventricular rate or blood pressure at ≥ 4-minute intervals (2.1, 2.2) Supraventricular tachycardia (SVT) or noncompensatory sinus tachycardia (2.1) Optional loading dose: 500 mcg per kg infused over one minute Then 50 mcg per kg per minute for the next 4 minutes Adjust dose as needed to a maximum of 200 mcg per kg per minute Additional loading doses may be administered Perioperative tachycardia and hypertension (2.2) Loading dose: 500 mcg per kg over 1 minute for gradual control (1 mg per kg over 30 seconds for immediate control) Then 50 mcg per kg per minute for gradual control (150 mcg per kg per minute for immediate control) adjusted to a maximum of 200 (tachycardia) or 300 (hypertension) mcg per kg per minute (2.2) Image1.jpg