What is the dose of epinephrine (Epi) for pediatric patients with anaphylaxis?

Epinephrine Dosing for Pediatric Anaphylaxis

For pediatric anaphylaxis, the recommended epinephrine dose is 0.01 mg/kg up to a maximum of 0.3 mg, administered intramuscularly into the lateral thigh (vastus lateralis muscle). 1

Weight-Based Dosing Guidelines

• For children weighing 30 kg (66 lbs) or less: 0.01 mg/kg (0.01 mL/kg) of 1:1000 solution, up to a maximum of 0.3 mg, administered intramuscularly into the anterolateral aspect of the thigh 2
• For children weighing more than 30 kg (66 lbs): 0.3 to 0.5 mg (0.3 to 0.5 mL) of 1:1000 solution intramuscularly into the anterolateral aspect of the thigh 2
• Doses may be repeated every 5 to 10 minutes as necessary if symptoms persist or recur 2

Autoinjector (EA) Recommendations

• For children weighing 7.5 to 25 kg (16.5-55 lbs): Use 0.15 mg epinephrine autoinjector 1
• For children weighing 25 kg (55 lbs) or more: Use 0.3 mg epinephrine autoinjector 1
• The transition from 0.15 mg to 0.3 mg dose should occur at approximately 25-30 kg (55-66 lbs) based on pharmacokinetic studies and expert consensus 1

Special Considerations for Infants

• For infants weighing less than 7.5 kg, the 0.15 mg autoinjector dose exceeds the recommended 0.01 mg/kg dose 1
• Despite this limitation, most pediatricians (80%) report they would prescribe the 0.15 mg autoinjector for infants weighing 10 kg (22 lbs) due to the challenges of accurate dosing with ampule/syringe methods 1
• Drawing up the correct dose from an ampule during an emergency is difficult and prone to errors, with studies showing 40-fold variations in doses drawn up by parents 1

For Cardiopulmonary Arrest During Anaphylaxis

• Initial resuscitation dose: 0.01 mg/kg (0.1 mL/kg of 1:10,000 solution) up to a maximum of 0.3 mg, repeated every 3-5 minutes for ongoing arrest 1
• Higher subsequent doses (0.1-0.2 mg/kg) may be considered for unresponsive asystole or pulseless electrical activity 1

Administration Route

• Intramuscular injection into the lateral thigh (vastus lateralis) is the preferred route for first-aid treatment of anaphylaxis 1, 3
• This route provides more rapid absorption and higher plasma levels compared to subcutaneous administration 4
• Intravenous epinephrine should be reserved for cardiac arrest or profound hypotension unresponsive to IM epinephrine and fluid resuscitation, and requires continuous hemodynamic monitoring 1, 5

Repeat Dosing

• If symptoms persist or recur, a second or third dose may be administered at 5-15 minute intervals 1
• Approximately 6-19% of pediatric patients require a second dose of epinephrine 1, 6
• Children requiring multiple doses of epinephrine are more likely to experience syncope and have comorbid allergic diseases 6
• Patients who receive multiple doses should be observed for at least 24 hours due to increased risk of biphasic reactions 6

Common Pitfalls to Avoid

• Delayed administration of epinephrine is associated with increased mortality in anaphylaxis 4, 3
• Subcutaneous administration results in delayed absorption compared to intramuscular injection 4
• Intravenous administration carries a higher risk of potentially lethal arrhythmias and should only be used in specific circumstances with appropriate monitoring 1, 5
• Autoinjector needle length may be too long for infants under 15 kg and too short for obese patients over 30 kg 7

Remember that epinephrine is the cornerstone of anaphylaxis management, and prompt administration is critical for preventing fatalities, especially in children 3.