Norepinephrine (Levophed) Dilution in D5W
The standard dilution for norepinephrine (Levophed) in D5W is to add 4 mg of norepinephrine to 250 mL of D5W to yield a concentration of 16 μg/mL. 1
Standard Dilution Methods
- For adult patients, the FDA-approved method is to add 4 mg (4 mL of a 1 mg/mL solution) of norepinephrine to 250 mL of D5W, resulting in a concentration of 16 μg/mL 1
- Alternative dilution: Add 1 mg (1 mL) of 1:1000 dilution of norepinephrine to 250 mL of D5W to yield a concentration of 4.0 μg/mL 2
- For anaphylaxis situations requiring continuous infusion, an alternative 1:100,000 solution can be prepared by adding 1 mg (1 mL) of norepinephrine in 100 mL of saline, administered at an initial rate of 30-100 mL/h (5-15 μg/min) 2
Administration Guidelines
- Norepinephrine should be administered as a continuous infusion through a large vein, preferably via central venous access 1
- Initial dosing typically starts at 2-3 mL/min (8-12 μg/min) of the standard 16 μg/mL solution, then titrated to maintain blood pressure 1
- Average maintenance dose ranges from 0.5-1 mL/min (2-4 μg/min) of the standard solution 1
- For peripheral administration (when central access is unavailable), more dilute solutions may be preferred to reduce the risk of extravasation 3
Important Considerations
- D5W is the preferred diluent for norepinephrine as it provides protection against significant loss of potency due to oxidation 1
- Administration in saline solution alone is not recommended by the FDA label 1
- Norepinephrine solutions (4 μg/mL and 16 μg/mL) in D5W are chemically stable for up to seven days at room temperature under ambient light 4
- Monitor for potential side effects including hypertension, arrhythmias, and tissue ischemia 3
Pediatric Considerations
- For pediatric patients, the "rule of 6" can be used: 0.6 × body weight (kg) = number of milligrams diluted to total 100 mL of saline; then 1 mL/h delivers 0.1 μg/kg/min 2, 3
- Pediatric dosing typically ranges from 0.1-1.0 μg/kg per minute, starting at the lowest dose and titrating to desired clinical effect 3
Precautions
- Be aware that severe hyponatremia and seizures have been reported with peripheral infusion of dilute norepinephrine (4 μg/mL) in D5W 5
- Ensure adequate volume resuscitation before and during norepinephrine administration 3
- Avoid abrupt withdrawal; infusions should be reduced gradually 1
- Do not mix norepinephrine with sodium bicarbonate or other alkaline solutions in the IV line, as they can inactivate the medication 3