Recommended Vasopressin Dosing
For septic shock, vasopressin should be administered at an initial dose of 0.01 units/minute and titrated up by 0.005 units/minute every 10-15 minutes to a maximum of 0.07 units/minute, while for post-cardiotomy shock, start at 0.03 units/minute with a maximum of 0.1 units/minute. 1
Indications and Dosing Guidelines
Vasopressin is primarily used as an adjunctive vasopressor in shock states, particularly when patients are refractory to catecholamines. The FDA-approved dosing varies by indication:
Septic Shock
- Initial dose: 0.01 units/minute
- Titration: Increase by 0.005 units/minute every 10-15 minutes until target blood pressure is reached
- Maximum dose: 0.07 units/minute 1
Post-Cardiotomy Shock
- Initial dose: 0.03 units/minute
- Titration: Increase by 0.005 units/minute every 10-15 minutes until target blood pressure is reached
- Maximum dose: 0.1 units/minute 1
Administration Considerations
- Vasopressin should be diluted in normal saline (0.9% sodium chloride) or 5% dextrose in water (D5W) prior to intravenous administration 1
- Discard unused diluted solution after 18 hours at room temperature or 24 hours under refrigeration 1
- Vasopressin is not recommended as a first-line agent but rather as an adjunct to norepinephrine 2
- After target blood pressure has been maintained for 8 hours without catecholamines, taper vasopressin by 0.005 units/minute every hour as tolerated 1
Safety Considerations and Monitoring
- Doses higher than 0.04 units/minute have not been associated with increased effectiveness and may be associated with higher adverse effects 3
- Cardiac arrests have been reported at doses of 0.05 units/minute or higher 3
- Vasopressin is not recommended for cardiogenic shock without ScvO2/CO monitoring 4
- Monitor for adverse effects including:
- Cardiac and peripheral ischemia
- Arrhythmias
- Hypertension
- Bowel ischemia 4
Timing of Vasopressin Addition
Recent evidence suggests earlier addition of vasopressin (within 3 hours of starting norepinephrine) may be beneficial:
- Associated with faster time to shock resolution (37.6 hours vs 60.7 hours) 5
- May decrease ICU length of stay 5
- A 2025 reinforcement learning study suggests more frequent and earlier use of vasopressin than current practice patterns, associated with reduced mortality 6
Special Populations
Pediatric Patients
- Low-dose arginine vasopressin (≤0.04 units/kg/min) has short-term hemodynamic benefits in children with vasodilatory shock 4
- Monitor renal function closely as pediatric patients may experience increased urea and creatinine levels and decreased urine output with longer duration or higher cumulative doses 7
- Platelet counts may be significantly lower during infusion 7
Important Caveats
- Always establish arterial line monitoring when using vasopressors 2
- Monitor parameters including blood pressure, heart rate, urine output, skin perfusion, mental status, lactate clearance, and renal and liver function tests 2
- Target mean arterial pressure (MAP) ≥65 mmHg 2
- Titrate to the lowest dose compatible with a clinically acceptable response 1
By following these evidence-based dosing guidelines and monitoring parameters, vasopressin can be safely and effectively used as an adjunctive vasopressor in appropriate shock states.