VASOSTRICT- vasopressin, unspecified injection
Par Pharmaceutical, Inc.
1 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.
2 DOSAGE AND ADMINISTRATION
2.1 Preparation of Diluted Solutions
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
Inspect parenteral drug products for particulate matter and discoloration prior to use, whenever solution and container permit.
3 DOSAGE FORMS AND STRENGTHS
Vasostrict� (vasopressin injection, USP) is a clear, practically colorless solution for intravenous administration available as 20 units/mL in a single dose vial and 200 units/10 mL (20 units/mL) in a multiple dose vial.
DESCRIPTION
Vasopressin is a polypeptide hormone that causes contraction of vascular and other smooth muscles and antidiuresis. Vasostrict� is a sterile, aqueous solution of synthetic arginine vasopressin for intravenous administration. The 1 mL solution contains vasopressin 20 units/mL, Water for Injection, USP, and sodium acetate buffer adjusted to a pH of 3.8. The 10 mL solution contains vasopressin 20 units/mL, chlorobutanol, NF 0.5% as a preservative, and Water for Injection, USP and, sodium acetate buffer adjusted to a pH of 3.8.
12 CLINICAL PHARMACOLOGY
12.1 Mechanism of Action
The vasoconstrictive effects of vasopressin are mediated by vascular V1 receptors. Vascular V1 receptors are directly coupled to phopholipase C, resulting in release of calcium, leading to vasoconstriction. In addition, vasopressin stimulates antidiuresis via stimulation of V2 receptors which are coupled to adenyl cyclase