Vasopressin

1 INDICATIONS AND USAGE Vasopressin injection is indicated to increase blood pressure in adults with vasodilatory shock who remain hypotensive despite fluids and catecholamines. • Vasopressin injection is indicated to increase blood pressure in adults with vasodilatory shock who remain hypotensive despite fluids and catecholamines. ( 1 )

2 DOSAGE AND ADMINISTRATION • Dilute 20 units/mL single dose vial contents with normal saline (0.9% sodium chloride) or 5% dextrose in water (D5W) to either 0.1 units/mL or 1 unit/mL for intravenous administration. Discard unused diluted solution after 18 hours at room temperature or 24 hours under refrigeration. ( 2.1 ) • Post-cardiotomy shock: 0.03 to 0.1 units/minute ( 2.2 ) • Septic shock: 0.01 to 0.07 units/minute ( 2.2 ) 2.1 Preparation of Solution Inspect parenteral drug products for particulate matter and discoloration prior to use, whenever solution and container permit. Vasopressin Injection Solution for Dilution, 20 units/mL Dilute Vasopressin injection in normal saline (0.9% sodium chloride) or 5% dextrose in water (D5W) prior to use for intravenous administration. Discard unused diluted solution after 18 hours at room temperature or 24 hours under refrigeration. Table 1 Preparation of diluted solutions Fluid restriction? Final concentration Mix Vasopressin injection Diluent No 0.1 units/mL 2.5 mL (50 units) 500 mL Yes 1 unit/mL 5 mL (100 units) 100 mL 2.2 Administration In general, titrate to the lowest dose compatible with a clinically acceptable response. The recommended starting dose is: Post-cardiotomy shock: 0.03 units/minute Septic Shock: 0.01 units/minute Titrate up by 0.005 units/minute at 10- to 15-minute intervals until the target blood pressure is reached. There are limited data for doses above 0.1 units/minute for postcardiotomy shock and 0.07 units/minute for septic shock. Adverse reactions are expected to increase with higher doses. After target blood pressure has been maintained for 8 hours without the use of catecholamines, taper vasopressin injection by 0.005 units/minute every hour as tolerated to maintain target blood pressure.

6 ADVERSE REACTIONS The following adverse reactions associated with the use of vasopressin were identified in the literature. Because these reactions are reported voluntarily from a population of uncertain size, it is not possible to estimate their frequency reliably or to establish a causal relationship to drug exposure. Bleeding/lymphatic system disorders: Hemorrhagic shock, decreased platelets, intractable bleeding Cardiac disorders: Right heart failure, atrial fibrillation, bradycardia, myocardial ischemia Gastrointestinal disorders: Mesenteric ischemia Hepatobiliary: Increased bilirubin levels Renal/urinary disorders: Acute renal insufficiency Vascular disorders: Distal limb ischemia Metabolic: Hyponatremia Skin: Ischemic lesions Postmarketing Experience Reversible diabetes insipidus [see Warnings and Precautions ( 5.2 )]. The most common adverse reactions include decreased cardiac output, bradycardia, tachyarrhythmias, hyponatremia and ischemia (coronary, mesenteric, skin, digital). ( 6 ) To report SUSPECTED ADVERSE REACTIONS, contact Fresenius Kabi USA, LLC at 1-800-551-7176 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

12.3 Pharmacokinetics Vasopressin plasma concentrations increase linearly with increasing infusion rates from 10 to 200 μU/kg/min. Steady state plasma concentrations are achieved after 30 minutes of continuous intravenous infusion. Distribution Vasopressin does not appear to bind plasma protein. The volume of distribution is 140 mL/kg. Elimination At infusion rates used in vasodilatory shock (0.01 to 0.1 units/minute), the clearance of vasopressin is 9 to 25 mL/min/kg in patients with vasodilatory shock. The apparent t 1/2 of vasopressin at these levels is ≤ 10 minutes. Metabolism Serine protease, carboxipeptidase and disulfide oxido-reductase cleave vasopressin at sites relevant for the pharmacological activity of the hormone. Thus, the generated metabolites are not expected to retain important pharmacological activity. Excretion Vasopressin is predominantly metabolized and only about 6% of the dose is excreted unchanged into urine. Specific Populations Pregnancy: Because of a spillover into blood of placental vasopressinase, the clearance of exogenous and endogenous vasopressin increases gradually over the course of a pregnancy. During the first trimester of pregnancy, the clearance is only slightly increased. However, by the third trimester the clearance of vasopressin is increased about 4-fold and at term up to 5-fold. After delivery, the clearance of vasopressin returns to preconception baseline within two weeks. Drug Interactions Indomethacin more than doubles the time to offset for vasopressin's effect on peripheral vascular resistance and cardiac output in healthy subjects [see Drug Interactions ( 7.2 )]. The ganglionic blocking agent tetra-ethylammonium increases the pressor effect of vasopressin by 20% in healthy subjects [see Drug Interactions ( 7.3 )]. Halothane, morphine, fentanyl, alfentanyl and sufentanyl do not impact exposure to endogenous vasopressin.