Norepinephrine Infusion Rate Calculation: 5-10 µg/min to mL/hour
For a norepinephrine infusion of 5-10 µg/min using the standard concentration of 16 µg/mL (4 mg in 250 mL D5W), set your infusion pump to 18.75-37.5 mL/hour.
Standard Concentration Preparation
- The FDA-approved standard dilution is 4 mg of norepinephrine in 250 mL of 5% dextrose injection, yielding a concentration of 16 µg/mL 1
- Dextrose-containing fluids are essential because they protect against significant loss of potency due to oxidation; administration in saline solution alone is not recommended 1
Calculation Method
For 16 µg/mL concentration:
- 5 µg/min ÷ 16 µg/mL × 60 min/hour = 18.75 mL/hour
- 10 µg/min ÷ 16 µg/mL × 60 min/hour = 37.5 mL/hour
Therefore, your pump range should be 18.75-37.5 mL/hour for the desired dose of 5-10 µg/min 2
Alternative Concentration for Specific Scenarios
- For anaphylaxis requiring continuous infusion, an alternative 1:100,000 solution (1 mg in 100 mL saline) creates a concentration of 10 µg/mL 2
- With this 10 µg/mL concentration, the same 5-10 µg/min dose would require 30-60 mL/hour 2
Clinical Context and Monitoring
- The FDA recommends initiating norepinephrine at 8-12 µg/min (2-3 mL/min of the standard dilution), which equals 120-180 mL/hour, then titrating down to a maintenance dose of 2-4 µg/min (0.5-1 mL/min or 30-60 mL/hour) 1
- Your requested dose of 5-10 µg/min falls within the typical maintenance range and is appropriate for ongoing blood pressure support 2
- Monitor blood pressure every 5-15 minutes during initial titration, targeting a mean arterial pressure of 65 mmHg 2
Critical Administration Requirements
- Central venous access is strongly preferred to minimize extravasation risk and tissue necrosis 2, 1
- If peripheral access is used temporarily, ensure the line is well-secured and monitor the site continuously for signs of infiltration 1
- Ensure adequate fluid resuscitation with at least 30 mL/kg crystalloid bolus before or concurrent with norepinephrine initiation 2