The Dept of Anaesthesia & Intensive Care, CUHK thanks

for an unrestricted education grant
Home Feedback Contents


Up ACE inhibitors Adenosine Anaphylaxis Antiarrhythmics Antibacterials Anticoagulants Anti-fibrinolytics Antifungals Antiplatelet drugs Anti-virals Beta2 agonists Ca antagonists Corticosteroids Erythropoietin Fosphenytoin Hydralazine Immunosuppressants Inotropes & vasopressors Insulin IV immunoglobulin Labetalol Mannitol Metoclopramide N-acetylcysteine Nesiritide Neuroleptic malignant syn Nitric oxide Nitroprusside Proton pump inhibitors Sedatives Serotonin syndrome Sucralfate Suxamethonium Theophylline Vasopressin


Mechanism of action

Haemodynamic effects

  • vasoconstriction mediated by effects on peripheral vasopressin receptors
    • in contrast to catecholamine mediated vasoconstriction effects are preserved during hypoxia and severe acidosis
    • effects greatest in splanchnic, muscular and cutaneous vessels
    • paradoxical vasodilatation may be seen in pulmonary, coronary and vertebrobasilar circulation
    • not known whether responsiveness to vasopressin varies between distributive, hypovolaemic and cardiogenic shock
  • reverses arginine vasopressin deficiency seen in prolonged shock. Whether this is important in its mechanism of action is unclear
  • additional mechanisms which may be important in septic shock:
    • blockade of activated ATP-sensitive K channels in vascular smooth muscle facilitating myocyte depolarization and vasoconstriction
    • attenuates stimulation of NO generation by endotoxin and IL-1ß inhibiting excessive vasodilatation
    • directly decreases intracellular concentrations of NO second messenger cGMP
    • enhances adrenergic responsiveness in endotoxaemia
    • stimulates synthesis of endothelin-I (potent endogenous vasoconstrictor)

Haemostatic effects

  • facilitates platelet aggregation and release of platelets from bone marrow
  • prostacyclin generation stimulated
  • increased tissue type plasminogen activator activity, factor VIII-related antigen activity, factor VIII coagulant activity and von Willebrand factor multimeres
  • arginine vasopressin and desmopressin induce pro-coagulant activity in healthy patients, haemophiliacs, and patients with renal and hepatic disease and after cardiac surgery. Whether or not arginine vasopressin causes clinically relevant haemostatic effects in the doses used for vasodilatory shock is unclear



  • glycolysis
  • gluconeogenesis
  • esterification and oxidation of free fatty acids
  • production of ketone bodies


  • increased resorption of free water
  • increased urine output during continuous arginine vasopressin infusion for distributive shock
    • mechanism may be selective (V1-mediated) vasoconstriction  of efferent arterioles resulting in increased glomerular filtration pressure. Alternative explanation is V2 -mediated natriuresis and diuresis

Hypothalamic-pituitary-adrenal function

  • stimulation of V3 receptors on anterior hypophysis stimulates release of ACTH and hence increased cortisol secretion

Clinical uses

Distributive shock

  • in distributive shock increases vasoconstriction, increasing SVR and decreasing cardiac output and allowing a reduction in norephinephrine dose
  • in a randomized controlled trial use of vasopressin 0.01-0.03 IU/min in addition to norepinephrine was not associated with an improved outcome compared to patients given norepinephrine alone
    • subgroup  analysis suggests that there may be a survival benefit for vasopressin in patients with less severe septic shock

Post cardiotomy shock

  • vasoconstriction resulting in increased SVR and MAP
  • variable effect on cardiac output

Adverse effects

  • animal studies have shown both coronary vasoconstriction and vasodilatation
  • in high doses in humans (5-20 times dose given in distributive shock) causes myocardial ischaemia
  • cutaneous and lingual ischaemia is common in patients with distributive shock treated with vasopressin but appears to be related to the underlying disease rather than the vasopressin
  • decreases splanchnic blood flow to a greater degree than norepinephrine
  • ?increased risk of sudden death when given at high doses

Further reading

Dünser MW et al. Management of vasodilatory shock. Defining the role of arginine vasopressin. Drugs, 2003;63(3):237-56

Russell JA et al. Vasopressin versus norepinephrine infusion in patients with septic shock. New Engl J Med 2008; 358: 877–887


©Charles Gomersall, January, 2018 unless otherwise stated. The author, editor and The Chinese University of Hong Kong take no responsibility for any adverse event resulting from the use of this webpage.
Copyright policy    Contributors