What is the recommended dose of epinephrine (adrenaline) for treating anaphylaxis?

Epinephrine Dosing for Anaphylaxis

For anaphylaxis treatment, epinephrine should be administered intramuscularly into the anterolateral thigh at a dose of 0.01 mg/kg of a 1:1000 (1 mg/mL) solution, up to 0.3 mg in children and 0.5 mg in adults. 1

Adult Dosing

• Adults and children ≥30 kg (66 lbs): 0.3 to 0.5 mg (0.3 to 0.5 mL of 1:1000 solution)
• Administer intramuscularly into the anterolateral thigh (vastus lateralis muscle)
• May repeat every 5-10 minutes as necessary if symptoms persist 2

Pediatric Dosing

• Children <30 kg (66 lbs): 0.01 mg/kg (0.01 mL/kg of 1:1000 solution), up to 0.3 mg
• Administer intramuscularly into the anterolateral thigh
• May repeat every 5-10 minutes as necessary 2

Autoinjector Selection Based on Weight

• 0.1 mg autoinjector: Infants weighing 7.5-15 kg (where available) 1
• 0.15 mg autoinjector: Children weighing 10-25 kg (22-55 lbs) 1
• 0.3 mg autoinjector: Children and adults weighing ≥25-30 kg (55-66 lbs) 1

Route of Administration

Intramuscular (IM) injection into the anterolateral thigh is the preferred route for first-line treatment of anaphylaxis for several important reasons:

• IM injection in the thigh provides faster absorption and higher plasma concentrations compared to subcutaneous injection 1
• Studies show peak plasma epinephrine concentrations are reached in approximately 8 minutes with IM thigh injection versus 34 minutes with subcutaneous deltoid injection 1

Special Considerations

For Infants (<15 kg)

• When 0.1 mg autoinjectors are not available, many physicians recommend using the 0.15 mg autoinjector for infants >7.5 kg rather than attempting to draw up doses manually 1
• The benefits of prompt administration with autoinjectors outweigh the risks of slight overdosing in these cases 1

For Refractory Anaphylaxis (Hospital Setting)

For patients not responding to initial IM doses:

• Consider epinephrine infusion: Add 1 mg (1 mL of 1:1000) to 1000 mL of 0.9% saline
• Start infusion at 2 μg/min (2 mL/min or 120 mL/h)
• Titrate up to 10 μg/min (10 mL/min or 600 mL/h) based on blood pressure, heart rate, and oxygenation 1

Common Pitfalls to Avoid

1. Route confusion: Intravenous epinephrine should be reserved only for profound hypotension or cardiac arrest, as it carries significant risk of arrhythmias 1

2. Concentration confusion: Ensure you're using the correct concentration (1:1000 or 1 mg/mL for IM injection) 3

3. Delayed administration: Failure to promptly inject epinephrine is a major contributor to anaphylaxis fatalities 4

4. Inadequate monitoring: After administering epinephrine, continue to monitor the patient as biphasic reactions may occur, requiring additional doses 1

5. Underdosing in obese patients: Standard autoinjector needle lengths may be insufficient to reach muscle in some obese patients 5

Remember that there are no absolute contraindications to epinephrine use in anaphylaxis, even in elderly patients or those with cardiovascular disease. The benefits of prompt administration outweigh the risks of adverse effects in this life-threatening condition 1.