Phenylephrine Hydrochloride

1 INDICATIONS & USAGE Phenylephrine hydrochloride Injection, 10 mg/mL is indicated for the treatment of clinically important hypotension resulting primarily from vasodilation in the setting of anesthesia. Phenylephrine hydrochloride Injection is an alpha-1 adrenergic receptor agonist indicated for the treatment of clinically important hypotension resulting primarily from vasodilation in the setting of anesthesia.

2 DOSAGE & ADMINISTRATION Phenylephrine hydrochloride Injection, 10 mg/mL, is injected intravenously either as a bolus or in a dilute solution as a continuous infusion. Dilute before administration. ( 2 ) Dosing for treatment of hypotension during anesthesia Bolus intravenous injection: 40 mcg to 100 mcg every 1 to 2 minutes as needed, not to exceed 200 mcg. (2) Intravenous infusion: 10 mcg/min to 35 mcg/min, titrating to effect, not to exceed 200 mcg/min. (2) Adjust the dose according to the pressor response (i.e., titrate to effect). (2) 2.1 General Dosage and Administration Instructions Phenylephrine hydrochloride Injection, 10 mg/mL must be diluted before administration as an intravenous bolus or continuous intravenous infusion to achieve the desired concentration: Bolus : Dilute with normal saline or 5% dextrose in water Continuous infusion : Dilute with normal saline or 5% dextrose in water. Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration. Do not use if the solution is colored or cloudy, or if it contains particulate matter. The diluted solution should not be held for more than 4 hours at room temperature or for more than 24 hours under refrigerated conditions. Discard any unused portion. During Phenylephrine hydrochloride injection administration: Correct intravascular volume depletion. Correct acidosis. Acidosis may reduce the effectiveness of phenylephrine. 2.2 Dosing for Treatment of Hypotension during Anesthesia The following are the recommended dosages for the treatment of hypotension during anesthesia. The recommended initial dose is 40 to 100 mcg administered by intravenous bolus. May administer additional boluses every 1-2 minutes as needed; not to exceed a total dosage of 200 mcg. If blood pressure is below the target goal, start a continuous intravenous infusion with an infusion rate of 10 to 35 mcg/minute; not to exceed 200 mcg/minute. Adjust dosage according to the blood pressure goal. 2.3 Prepare a 100 mcg/mL Solution for Bolus Intravenous Administration For bolus intravenous administration, prepare a solution containing a final concentration of 100 mcg/mL of Phenylephrine hydrochloride injection : Withdraw 10 mg (1 mL of 10 mg/mL) of Phenylephrine hydrochloride injection and dilute with 99 mL of 5% Dextrose Injection, USP or 0.9% Sodium Chloride Injection, USP. Withdraw an appropriate dose from the 100 mcg/mL solution prior to bolus intravenous administration. 2.4 Prepare a Solution for Continuous Intravenous Administration For continuous intravenous infusion, prepare a solution containing a final concentration of 20 mcg/mL of Phenylephrine hydrochloride injection in 5% Dextrose Injection, USP or 0.9% Sodium Chloride Injection, USP: Withdraw 10 mg (1 mL of 10 mg/mL) of Phenylephrine hydrochloride injection and dilute with 500 mL of 5% Dextrose Injection, USP or 0.9% Sodium Chloride Injection, USP. 2.5 Directions for Dispensing from Pharmacy Bulk Vial The Pharmacy Bulk Vial is intended for dispensing of single doses to multiple patients in a pharmacy admixture program and is restricted to the preparation of admixtures for infusion. Each closure shall be penetrated only one time with a suitable sterile transfer device or dispensing set that allows measured dispensing of the contents. The Pharmacy Bulk Vial is to be used only in a suitable work area such as a laminar flow hood (or an equivalent clean air compounding area). Dispensing from a pharmacy bulk vial should be completed within 4 hours after the vial is penetrated.

6 ADVERSE REACTIONS Adverse reactions to Phenylephrine hydrochloride injection are primarily attributable to excessive pharmacologic activity. Adverse reactions reported in published clinical studies, observational trials, and case reports of Phenylephrine hydrochloride injection are listed below by body system. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to estimate their frequency reliably or to establish a causal relationship to drug exposure. Cardiac disorders : Reflex bradycardia, lowered cardiac output, ischemia, hypertension, arrhythmias Gastrointestinal disorders : Epigastric pain, vomiting, nausea Nervous system disorders : Headache, blurred vision, neck pain, tremors Vascular disorders : Hypertensive crisis Respiratory, Thoracic and Mediastinal Disorders : Dyspnea Skin and subcutaneous tissue disorders : Pruritis Most common adverse reactions during treatment: nausea, vomiting, and headache. ( 6 ) To report SUSPECTED ADVERSE REACTIONS, contact Provepharm Inc., at 1–833-727-6556 or [email protected] or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

12.3 Pharmacokinetics Following an intravenous infusion of phenylephrine hydrochloride, the observed effective half -life was approximately 5 minutes. The steady-state volume of distribution of approximately 340 L suggests a high distribution into organs and peripheral tissues. The average total serum clearance is approximately 2100 mL/min. The observed phenylephrine plasma terminal elimination half-life was 2.5 hours. Phenylephrine is metabolized primarily by monoamine oxidase and sulfotransferase. After intravenous administration of radiolabeled phenylephrine, approximately 80% of the total dose was eliminated within first 12 h; and approximately 86% of the total dose was recovered in the urine within 48 h. The excreted unchanged parent drug was 16% of the total dose in the urine at 48 h post intravenous administration. There are two major metabolites, with approximately 57 and 8% of the total dose excreted as m-hydroxymandelic acid and sulfate conjugates, respectively. The metabolites are considered not pharmacologically active.