Epinephrine Drip Dosing for Severe Allergic Reactions/Anaphylaxis
For adults with severe allergic reactions or anaphylaxis, the recommended starting dose for an epinephrine drip is 1-4 mcg/min, which can be titrated up to a maximum of 10 mcg/min based on clinical response and side effects. 1
Preparation Methods for Epinephrine Infusions
There are two standard methods to prepare an epinephrine infusion for adults:
Method 1: Standard Concentration
- Add 1 mg (1 mL) of 1:1000 epinephrine to 250 mL of D5W to yield a concentration of 4.0 mcg/mL 1
- Initial infusion rate: 1-4 mcg/min (15-60 drops/min with microdrop apparatus) 1
- Can be titrated up to maximum of 10 mcg/min based on clinical response 1
Method 2: Alternative Concentration (with Infusion Pump)
- Add 1 mg (1 mL) of 1:1000 epinephrine to 100 mL of saline to create a 1:100,000 solution 1
- Initial infusion rate: 30-100 mL/hr (5-15 mcg/min) 1
- Titrate up or down based on clinical response or epinephrine side effects 1
Important Considerations and Precautions
Indications for IV Epinephrine
- IV epinephrine should only be administered in specific circumstances: 1
- Cardiac arrest
- Profound hypotension unresponsive to IV fluids and IM epinephrine
- Failure to respond to several injected doses of epinephrine
Monitoring Requirements
- Continuous hemodynamic monitoring is essential when administering IV epinephrine 1
- In settings without hemodynamic monitoring, use available means: 1
- Every-minute blood pressure measurements
- Continuous pulse monitoring
- ECG monitoring if available
Clinical Efficacy
- In clinical studies, most patients (18/19) with anaphylaxis showed symptomatic improvement and systolic BP >90 mmHg within 5 minutes of epinephrine infusion 1
Pediatric Dosing
- For children, the recommended dose is 0.01 mg/kg (0.1 mL/kg of 1:10,000 solution; maximum 0.3 mg) 1
- Alternative pediatric dosing using "rule of 6": 0.6 × body weight (kg) = mg diluted to total 100 mL saline; then 1 mL/hr delivers 0.1 mcg/kg/min 1
Potential Adverse Effects
- Tachyarrhythmias/ectopic beats 1
- Hypertension 1
- Risk of potentially lethal arrhythmias (reason for restricted use) 1
- Extravasation can cause severe skin injury 1
First-Line Treatment Before Drip Consideration
- IM epinephrine (0.01 mg/kg of 1:1000 solution, max 0.3-0.5 mg) is the first-line treatment for anaphylaxis 1, 2
- IM injections should be administered in the lateral thigh (vastus lateralis) 1, 3
- Additional IM doses can be given every 5-15 minutes if symptoms persist 1, 4
- IV epinephrine infusion should only be considered after failure of IM epinephrine and volume resuscitation 1
Common Pitfalls to Avoid
- Delaying epinephrine administration (increases mortality risk) 5, 4
- Using subcutaneous instead of intramuscular route (delayed onset of action) 5
- Starting with IV epinephrine before trying IM epinephrine (increased risk of adverse effects) 1
- Relying on antihistamines or corticosteroids as first-line treatment (they are adjunctive only) 1, 4
- Inadequate monitoring during epinephrine infusion 1