Epinephrine Dosing for Anaphylaxis, Cardiac Arrest, and Hypotension
Anaphylaxis (First-Line Treatment)
For anaphylaxis, administer 0.3 to 0.5 mg of epinephrine (1:1000 concentration) intramuscularly into the anterolateral thigh in adults, repeated every 5 to 15 minutes as needed. 1, 2
Intramuscular Dosing (Preferred Route)
- Adults and children ≥30 kg: 0.3 to 0.5 mg (0.3 to 0.5 mL of 1:1000) IM into anterolateral thigh 1, 3
- Children <30 kg: 0.01 mg/kg (0.01 mL/kg of 1:1000), maximum 0.3 mg IM into anterolateral thigh 1, 3
- Repeat dosing: Every 5 to 15 minutes as needed based on clinical response 1, 2
- The intramuscular route in the lateral thigh produces rapid peak plasma concentrations (8 ± 2 minutes) compared to subcutaneous injection (34 ± 14 minutes) 4
Autoinjector Dosing (Community Settings)
- 0.15 mg autoinjector: For patients weighing 7.5 to 25 kg (16.5 to 55 lbs) 1
- 0.3 mg autoinjector: For patients weighing ≥25 kg (≥55 lbs) 1
Intravenous Epinephrine for Anaphylactic Shock
When IV access is already established and the patient has anaphylactic shock, administer 0.05 to 0.1 mg (50 to 100 mcg) of epinephrine (1:10,000 concentration) as a slow IV bolus. 1
- IV bolus dose: 0.05 to 0.1 mg (0.5 to 1 mL of 1:10,000) given slowly 1
- This represents 5% to 10% of the cardiac arrest dose 1
- Pediatric IV dose: 0.01 mg/kg (0.1 mL/kg of 1:10,000; maximum 0.3 mg) given slowly over several minutes with continuous hemodynamic monitoring 4
Epinephrine Infusion for Refractory Anaphylaxis
For persistent hypotension or when more than three boluses have been administered, initiate an epinephrine infusion at 5 to 15 mcg/min (0.05 to 0.1 mcg/kg/min in children). 1, 4
- Adult infusion: 5 to 15 mcg/min, titrated to blood pressure and clinical response 1
- Pediatric infusion: 0.05 to 0.1 mcg/kg/min (1-4 mcg/min), using 1 mg epinephrine in 250 mL D5W (4 mcg/mL concentration) 4
- Continuous hemodynamic monitoring is mandatory during IV administration 4
Cardiac Arrest
In cardiac arrest (including anaphylaxis-induced arrest), administer standard ACLS epinephrine dosing: 1 mg IV/IO every 3 to 5 minutes. 1
Standard Cardiac Arrest Dosing
- Adult dose: 1 mg (1 mL of 1:1000 or 10 mL of 1:10,000) IV/IO every 3 to 5 minutes 1
- Pediatric dose: 0.01 mg/kg (0.1 mL/kg of 1:10,000; maximum single dose 1 mg) IV/IO every 3 to 5 minutes 4
- Standard BLS and ACLS protocols take priority in anaphylaxis-induced cardiac arrest 1
Hypotension Management
Refractory Hypotension Despite Epinephrine
For hypotension refractory to epinephrine and fluid resuscitation, add norepinephrine infusion at 0.05 to 0.5 mcg/kg/min. 4
- Norepinephrine infusion: 0.05 to 0.5 mcg/kg/min for persistent hypotension 4
- Vasopressin: Consider 1 to 2 IU bolus with or without infusion (2 units/h) for refractory hypotension 4
- Dopamine (pediatric): 2 to 20 mcg/kg/min titrated to maintain systolic BP >90 mmHg 4
Special Population: Beta-Blocker Patients
Patients on beta-blockers with refractory symptoms require IV glucagon 1 to 2 mg (pediatric: 20-30 mcg/kg, maximum 1 mg) over 5 minutes. 4
Critical Pitfalls to Avoid
- Never delay epinephrine administration — delayed injection is associated with fatalities 4, 5, 6
- Never substitute antihistamines or corticosteroids for epinephrine as first-line treatment 1, 4
- Do not confuse anaphylaxis dosing with cardiac arrest dosing — this iatrogenic error can cause lethal cardiac complications from inappropriate IV push of 1 mg doses 7, 8
- Avoid subcutaneous administration — it has delayed onset compared to intramuscular injection 4, 5
- Do not inject into buttocks, digits, hands, or feet — risk of tissue necrosis and inadequate absorption 3
- Ensure continuous monitoring when using IV epinephrine — risk of arrhythmias and hypertensive crisis 4, 3