Basics of Vasopressors, Part 3: Vasopressin

About vasopressin 

  • Mechanism of action: V1, VagonismV1 is present on blood vessels and results in peripheral vasoconstriction. This results in an increase in preload, afterload, and SVR. V2 is located in the kidneys and promotes the retention of water; remember that vasopressin and ADH are synonyms! This increases plasma volume, which can increase blood pressure.  

  • Uses: as an adjunct to most other pressors (usually to help wean down norepinephrine). May be a good pressor for hepatorenal syndrome, as patients who received norepinephrine/vasopressin rather than just norepinephrine were less likely to require dialysis.  

  • Avoid: peripherally, as it can cause ischemia that has no antidote. Also avoid for hypoNa, as water retention at the level of the kidneys can worsen hypoNaVasopressin at lower doses than a pressor dose is actually used for hyperNa, specifically DI.


Our 'obligatory' table of pressors, for comparison:




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