What is the appropriate intramuscular epinephrine (adrenaline) dose for a 1‑year‑old child weighing approximately 10 kg with anaphylaxis?

Standard Epinephrine Dosing for a One-Year-Old with Anaphylaxis

For a 1-year-old child weighing approximately 10 kg experiencing anaphylaxis, administer 0.1 mg (0.1 mL of 1:1000 solution) of epinephrine intramuscularly into the anterolateral thigh, which can be repeated every 5-10 minutes as needed until symptoms resolve. 1, 2

Weight-Based Dosing Calculation

• The standard pediatric dose is 0.01 mg/kg of 1:1000 (1 mg/mL) epinephrine solution administered intramuscularly 1, 2
• For a 10 kg child: 10 kg × 0.01 mg/kg = 0.1 mg (0.1 mL of 1:1000 solution) 1, 2
• The maximum single dose for children under 30 kg is 0.3 mg (0.3 mL) 2

Administration Technique

• Inject intramuscularly into the anterolateral aspect of the mid-thigh (vastus lateralis muscle) through clothing if necessary 1, 2
• Use a needle at least 1/2 to 5/8 inch long to ensure intramuscular delivery 2
• Hold the child's leg firmly in place and limit movement before and during injection to minimize injury risk 2
• The intramuscular thigh route achieves peak plasma concentrations in 8±2 minutes, compared to 34±14 minutes with subcutaneous deltoid injection 1, 3

Repeat Dosing Protocol

• Repeat the same dose every 5-10 minutes if symptoms fail to resolve or worsen 1, 2
• Approximately 6-28% of pediatric patients require a second dose 3
• There is no maximum number of doses—continue dosing based on clinical response 1, 3
• Do not administer repeated injections at the same site, as vasoconstriction may cause tissue necrosis 2

Autoinjector Considerations for This Age Group

While the weight-based calculation yields 0.1 mg as the ideal dose, practical considerations exist regarding autoinjector availability:

• A 0.1 mg autoinjector is now available and provides the most accurate dosing for a 10 kg child 1
• The 0.15 mg autoinjector is commonly prescribed for children 10-25 kg (representing a 1.5-fold overdose for a 10 kg child), though this exceeds ideal dosing 1
• Studies show that 95% of prescriptions for infants 6-12 months of age are for the 0.15 mg autoinjector, reflecting physician preference for certainty of delivery over perfect dosing accuracy 1
• The American Academy of Pediatrics acknowledges that for children weighing 10 kg, the speed and precision of a 0.15 mg autoinjector may justify dosing trade-offs compared to the error-prone ampule/syringe/needle technique 1

Critical Safety Points

• Epinephrine is the only first-line treatment for anaphylaxis—antihistamines and corticosteroids are second-line adjuncts only 1, 4
• Delayed epinephrine administration is associated with fatalities; administer immediately upon recognition of anaphylaxis 1, 5, 6, 4
• There is no absolute contraindication to epinephrine use in anaphylaxis 1
• Monitor clinically for reaction severity and potential cardiac effects with each dose 2

Common Pitfalls to Avoid

• Do not use subcutaneous route: onset of action is delayed compared to intramuscular administration 5
• Do not confuse concentrations: always use 1:1000 (1 mg/mL) for intramuscular injection; 1:10,000 is reserved for intravenous use only 1
• Do not delay for IV access: intramuscular epinephrine is safer and preferred for first-line treatment 3
• Do not stop at one dose prematurely: if symptoms persist or progress after 5-10 minutes, repeat the dose 1, 3
• Do not substitute epinephrine inhalation: studies show children cannot inhale sufficient epinephrine to achieve therapeutic plasma concentrations 7

Concurrent Management

After administering epinephrine:

• Call 911 or activate emergency medical services immediately 3
• Position the child supine with legs elevated; never allow standing or walking as this increases mortality risk 3
• Administer supplemental oxygen and establish IV access for fluid resuscitation if needed 3
• Consider adjunctive H1 antihistamine (diphenhydramine 1-2 mg/kg, maximum 50 mg) only after epinephrine 1, 8
• Consider H2 antihistamine and corticosteroids as second-line therapies 1

When to Escalate Beyond Intramuscular Epinephrine

• If the patient fails to respond to multiple intramuscular doses, consider transitioning to intravenous epinephrine infusion (0.1-1.0 mcg/kg/min, titrated to effect) 1
• IV epinephrine requires continuous hemodynamic monitoring and should only be administered by experienced providers 1