Racemic Epinephrine Concentration for Croup

Standard Concentration and Dosing

• The American Academy of Pediatrics recommends 0.05 mL/kg (maximum 0.5 mL) of the 2.25% solution diluted in 2 mL of normal saline for nebulization in children with croup, which contains 11.25 mg of racepinephrine per 0.5 mL 1, 2
• Many institutions use a standard 0.5 mL dose of racemic epinephrine for all patients regardless of weight, which simplifies administration without compromising safety 1, 2

Alternative: L-Epinephrine Substitution

• If racemic epinephrine is unavailable, L-epinephrine (1:1000 concentration) can be substituted at 0.5 mL/kg up to 5 mL administered by nebulizer 1, 2

Clinical Context and Efficacy

• The therapeutic effect of nebulized epinephrine is temporary, which is why observation for at least 2 hours after each dose is recommended before making disposition decisions 3, 4, 5
• Recent evidence suggests that admission should be considered after 3 total doses of racemic epinephrine rather than the traditional 2 doses, as 80% of admitted patients require no further airway interventions 3, 4, 5

Critical Safety Points

• Do not confuse racemic epinephrine 2.25% solution with standard epinephrine 1:1000 or 1:10,000 concentrations used for other indications—these are entirely different formulations with different dosing 1, 2
• Racemic epinephrine for croup is administered only by nebulization, never by intramuscular, subcutaneous, or intravenous routes 1, 2