Get your patient on Vasopressin - Vasopressin injection (Vasopressin)
Vasopressin - Vasopressin injection prescribing information
INDICATIONS AND USAGE
Vasopressin Injection, USP is indicated to increase blood pressure in adults with vasodilatory shock who remain hypotensive despite fluids and catecholamines.
DOSAGE AND ADMINISTRATION
Preparation of Solution
Inspect parenteral drug products for particulate matter and discoloration prior to use, whenever solution and container permit.
Dilute Vasopressin Injection, USP 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, USP | Diluent | ||
| No | 0.1 units/mL | 2.5 mL (50 units) | 500 mL |
| Yes | 1 unit/mL | 5 mL (100 units) | 100 mL |
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
Tritate 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.
DOSAGE FORMS AND STRENGTHS
Vasopressin Injection, USP is a clear, practically colorless solution for intravenous administration available as 20 units/mL in a single dose vial. To be used after dilution.
USE IN SPECIFIC POPULATIONS
Pregnancy
Risk Summary There are no available data on Vasopressin Injection, USP use in pregnant women to inform a drug associated risk of major birth defects, miscarriage, or adverse maternal or fetal outcomes. Animal reproduction studies have not been conducted with vasopressin.
Clinical Considerations Dose adjustments during pregnancy and the postpartum period: Because of increased clearance of vasopressin in the second and third trimester, the dose of Vasopressin Injection, USP may need to be increased [ see Dosage and Administration (2.2 ) and Clinical Pharmacology (12.3 ) ].
Maternal adverse reactions : Vasopressin Injection, USP may produce tonic uterine contractions that could threaten the continuation of pregnancy.
Lactation
There are no data on the presence of vasopressin injection in either human or animal milk, the effects on the breastfed infant, or the effects on milk production.
Pediatric Use
Safety and effectiveness of Vasopressin Injection, USP in pediatric patients with vasodilatory shock have not been established.
Geriatric Use
Clinical studies of vasopressin did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. Other reported clinical experience has not identified differences in responses between the elderly and younger patients. In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy [see Warnings and Precautions (5 ) , Adverse Reactions (6 ) , and Clinical Pharmacology (12.3 ) ].
CONTRAINDICATIONS
Vasopressin Injection, USP 1 mL single dose vial is contraindicated in patients with known allergy or hypersensitivity to 8‑L-arginine vasopressin or chlorobutanol.
WARNINGS AND PRECAUTIONS
Worsening Cardiac Function
A decrease in cardiac index may be observed with the use of Vasopressin Injection, USP.
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.
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 ) ].
DRUG INTERACTIONS
Catecholamines
Use with catecholamines is expected to result in an additive effect on mean arterial blood pressure and other hemodynamic parameters. Hemodynamic monitoring is recommended; adjust the dose of vasopressin as needed.
Indomethacin
Use with indomethacin may prolong the effect of Vasopressin Injection, USP on cardiac index and systemic vascular resistance. Hemodynamic monitoring is recommended; adjust the dose of vasopressin as needed [see Clinical Pharmacology (12.3 ) ].
Ganglionic Blocking Agents
Use with ganglionic blocking agents may increase the effect of Vasopressin Injection, USP on mean arterial blood pressure. Hemodynamic monitoring is recommended; adjust the dose of vasopressin as needed [ see Clinical Pharmacology (12.3 ) ].
Drugs Suspected of Causing SIADH
Use with drugs suspected of causing SIADH (e.g., SSRIs, tricyclic antidepressants, haloperidol, chlorpropamide, enalapril, methyldopa, pentamidine, vincristine, cyclophosphamide, ifosfamide, felbamate) may increase the pressor effect in addition to the antidiuretic effect of Vasopressin Injection, USP. Hemodynamic monitoring is recommended; adjust the dose of vasopressin as needed.
Drugs Suspected of Causing Diabetes Insipidus
Use with drugs suspected of causing diabetes insipidus (e.g., demeclocycline, lithium, foscarnet, clozapine) may decrease the pressor effect in addition to the antidiuretic effect of Vasopressin Injection, USP. Hemodynamic monitoring is recommended; adjust the dose of vasopressin as needed.
DESCRIPTION
Vasopressin is a polypeptide hormone. Vasopressin Injection, USP is a sterile, aqueous solution of synthetic arginine vasopressin for intravenous administration.
The 1 mL solution contains vasopressin 20 units/mL, chlorobutanol, NF 0.5% as a preservative, and Water for Injection, USP adjusted with acetic acid to pH 3.4-3.6.
The chemical name of vasopressin is Cyclo (1-6) L-Cysteinyl-L-Tyrosyl-L-Phenylalanyl-LGlutaminyl-L-Asparaginyl-L-Cysteinyl-L-Prolyl-L-Arginyl-L-Glycinamide. It is a white to off-white amorphous powder, freely soluble in water. The structural formula is:
Molecular Formula: C 46 H 65 N 15 O 12 S 2 Molecular Weight: 1084.23
One mg is equivalent to 530 units.
CLINICAL PHARMACOLOGY
Mechanism of Action
Vasopressin causes vasoconstriction by binding to V 1 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 V 2 receptors which are coupled to adenyl cyclase.
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 V 1 -receptors and release of prolactin and ACTH via V 3 receptors. At lower concentrations typical for the antidiuretic hormone vasopressin inhibits water diuresis via renal V 2 receptors. In addition, vasopressin has been demonstrated to cause vasodilation in numerous vascular beds that are mediated by V 2 , V 3 , 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.
Pharmacokinetics
Vasopressin plasma concentrations increase linearly with increasing infusion rates from 10 to 200 ÎĽU/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.
NONCLINICAL TOXICOLOGY
Carcinogenesis, Mutagenesis, Impairment of Fertility
No formal carcinogenicity or fertility studies with vasopressin have been conducted in animals. Vasopressin was found to be negative in the in vitro bacterial mutagenicity (Ames) test and the in vitro Chinese hamster ovary (CHO) cell chromosome aberration test. In mice, vasopressin has been reported to have an effect on function and fertilizing ability of spermatozoa.
Animal Toxicology and/or Pharmacology
No toxicology studies were conducted with vasopressin.
CLINICAL STUDIES
Increases in systolic and mean blood pressure following administration of vasopressin were observed in 7 studies in septic shock and 8 in post-cardiotomy vasodilatory shock.
HOW SUPPLIED/STORAGE AND HANDLING
Vasopressin Injection, USP is a clear, practically colorless solution for intravenous administration available as:
A carton of 10 single dose vials. Each vial contains vasopressin 1 mL at 20 units/mL.
NDC 0548-9701-00 Stock No. 9701
Store between 2°C and 8°C (36°F and 46°F). Do not freeze.
Vials may be held up to 12 months upon removal from refrigeration to room temperature storage conditions (20°C to 25°C [68°F to 77°F], USP Controlled Room Temperature), anytime within the labeled shelf life. Once removed from refrigeration, unopened vial should be marked to indicate the revised 12 month expiration date. If the manufacturer’s original expiration date is shorter than the revised expiration date, then the shorter date must be used. Do not use Vasopressin Injection, USP beyond the manufacturer’s expiration date stamped on the vial. The storage conditions and expiration periods are summarized in the following table.
| Unopened Refrigerated 2°C to 8°C (36°F to 46°F) | Unopened Room Temperature 20°C to 25°C (68°F to 77°F) Do not store above 25°C (77°F) | Opened (After First Puncture) | |
| 1 mL Vial | Until manufacturer expiration date | 12 months or until manufacturer expiration date, whichever is earlier | N/A |
Mechanism of Action
Vasopressin causes vasoconstriction by binding to V 1 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 V 2 receptors which are coupled to adenyl cyclase.
