Dexamethasone Dosing for Pediatric Croup

Dosing Recommendations

The American Academy of Pediatrics recommends administering a single dose of dexamethasone 0.6 mg/kg (maximum 16 mg) orally for pediatric croup, which is the standard recommended dose 1
For a typical 2-year-old weighing approximately 12-13 kg, the standard dose translates to roughly 7-8 mg of dexamethasone 1
Oral administration is preferred when the child can tolerate it, as it is equally effective as intramuscular injection and avoids the pain of injection 1
All three routes (oral, IM, IV) are equally effective for croup treatment 1

Onset of action occurs as early as 30 minutes after administration 1
Duration of action is approximately 24-72 hours, providing sustained relief 1
No tapering is required for the single-dose regimen, and it does not cause significant adrenal suppression 1

For moderate to severe croup with significant respiratory distress, consider adding nebulized epinephrine while waiting for dexamethasone to take effect 1, 2
Nebulized epinephrine dose: 0.5 mL/kg of 1:1000 solution (maximum 5 mL) 1, 2
Epinephrine provides immediate but short-term symptom improvement, while dexamethasone provides longer-lasting relief 1

Dexamethasone is specifically for croup (laryngotracheobronchitis), not for non-specific cough or chronic cough 3
The characteristic "seal-like barking cough" is a classic recognizable feature of croup 4
For severe croup requiring repeat dosing, administer another dose of dexamethasone plus nebulized epinephrine regardless of timing of the initial dose 1