100 ML vasopressin (USP) 0.2 UNT/ML Injection

INDICATIONS AND USAGE Vasostrict ® is indicated to increase blood pressure in adults with vasodilatory shock (e.g., post-cardiotomy or sepsis) who remain hypotensive despite fluids and catecholamines. Vasostrict ® is indicated to increase blood pressure in adults with vasodilatory shock (e.g., post-cardiotomy or sepsis) who remain hypotensive despite fluids and catecholamines. ( 1 )

DOSAGE AND ADMINISTRATION Dilute 20 units/mL single dose vial or 200 units/10 mL (20 units/mL) multiple 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 ) The 20 units/100 mL, 40 units/100 mL, 60 units/100 mL and 50 units/50 mL single dose vials do not require further dilution prior to administration. ( 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. Vasostrict ® Solution for Dilution, 20 units/mL and 200 units/10 mL (20 units/mL) Dilute Vasostrict ® 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 Vasostrict ® Diluent No 0.1 units/mL 2.5 mL (50 units) 500 mL Yes 1 unit/mL 5 mL (100 units) 100 mL Vasostrict ® Premixed Solution, 20 units/100 mL (0.2 units/mL), 40 units/100 mL (0.4 units/mL), 60 units/100 mL (0.6 units/mL) and 50 units/50 mL (1 unit/mL) This product does not require further dilution prior to administration. 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 post-cardiotomy 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.

WARNINGS AND PRECAUTIONS Can worsen cardiac function. ( 5.1 ) Reversible diabetes insipidus ( 5.2 ) 5.1 Worsening Cardiac Function A decrease in cardiac index may be observed with the use of Vasopressin Injection, USP. 5.2 Reversible Diabetes Insipidus Patients may experience reversible diabetes insipidus, manifested by the development of polyuria, a dilute urine, and hypernatremia, after cessation of treatment with vasopressin. Monitor serum electrolytes, fluid status, and urine output after vasopressin discontinuation. Some patients may require readministration of vasopressin or administration of desmopressin to correct fluid and electrolyte shifts.

CONTRAINDICATIONS Vasostrict ® 10 mL multiple dose vial is contraindicated in patients with known allergy or hypersensitivity to 8‑L-arginine vasopressin or chlorobutanol. The 1 mL single dose vial, 50 mL and 100 mL pre-mixed single dose vial does not contain chlorobutanol and is therefore contraindicated only in patients with a known allergy or hypersensitivity to 8-L-arginine vasopressin. Vasostrict ® 10 mL multiple dose vial is contraindicated in patients with known allergy or hypersensitivity to 8‑L-arginine vasopressin or chlorobutanol. The 1 mL single dose vial, 50 mL and 100 mL pre-mixed single dose vial does not contain chlorobutanol and is therefore contraindicated only in patients with a known allergy or hypersensitivity to 8-L-arginine vasopressin. (4)

Mechanism of Action Vasopressin causes vasoconstriction by binding to V1 receptors on vascular smooth muscle coupled to the Gq/11-phospholipase C-phosphatidyl-inositol-triphosphate pathway, resulting in the release of intracellular calcium. In addition, vasopressin stimulates antidiuresis via stimulation of V2 receptors which are coupled to adenyl cyclase. 12.2 Pharmacodynamics At therapeutic doses exogenous vasopressin elicits a vasoconstrictive effect in most vascular beds including the splanchnic, renal and cutaneous circulation. In addition, vasopressin at pressor doses triggers contractions of smooth muscles in the gastrointestinal tract mediated by muscular V1-receptors and release of prolactin, ACTH and catecholamines via V3 receptors. At lower concentrations typical for the antidiuretic hormone vasopressin inhibits water diuresis via renal V2 receptors. In addition, vasopressin has been demonstrated to cause vasodilation in numerous vascular beds that is mediated by V2, V3, oxytocin and purinergic P2 receptors. In patients with vasodilatory shock, vasopressin in therapeutic doses increases systemic vascular resistance and mean arterial blood pressure and reduces the dose requirements for norepinephrine. Vasopressin tends to decrease heart rate and cardiac output. The pressor effect is proportional to the infusion rate of exogenous vasopressin. The pressor effect reaches its peak within 15 minutes. After stopping the infusion, the pressor effect fades within 20 minutes. There is no evidence for tachyphylaxis or tolerance to the pressor effect of vasopressin in patients. 12.3 Pharmacokinetics Vasopressin plasma concentrations increase linearly with increasing infusion rates from 10 microunits/kg/min to 200 microunits/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 units/minute to 0.1 units/minute), the clearance of vasopressin is 9 to 25 mL/min/kg in patients with vasodilatory shock. The apparent t1/2 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 pre-conception 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.