What is the recommended dose of dexamethasone (corticosteroid) for a 2-year-old with possible croup or a seal-like barking cough?

Dexamethasone Dosing for a 2-Year-Old with Possible Croup

Administer a single dose of dexamethasone 0.6 mg/kg (maximum 16 mg) orally, which is the standard recommended dose for pediatric croup. 1

Dosing Specifics

• Standard dose: 0.6 mg/kg (maximum 16 mg) given as a single dose 1
• For a typical 2-year-old weighing approximately 12-13 kg, this 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

Lower Dose Alternative

• Dexamethasone 0.15 mg/kg may be equally effective as the standard 0.6 mg/kg dose for moderate to severe croup 2, 3
• A Cochrane review found little to no difference between 0.15 mg/kg and 0.6 mg/kg doses at 2 hours (high-certainty evidence) and probably no difference at 6 hours (moderate-certainty evidence) 3
• However, the 0.6 mg/kg dose is still the standard recommendation from the American Academy of Pediatrics 1

Clinical Onset and Duration

• 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

Adjunctive Therapy for Severe Cases

• For moderate to severe croup with significant respiratory distress (prominent stridor, significant retractions, agitation), consider adding nebulized epinephrine while waiting for dexamethasone to take effect 1, 4
• Nebulized epinephrine dose: 0.5 mL/kg of 1:1000 solution (maximum 5 mL) 1, 4
• Epinephrine provides immediate but short-term symptom improvement, while dexamethasone provides longer-lasting relief 1

Important Clinical Caveats

• Dexamethasone is specifically for croup (laryngotracheobronchitis), not for non-specific cough or chronic cough 5
• The characteristic "seal-like barking cough" is a classic recognizable feature of croup 6
• If the child requires two epinephrine treatments, hospitalization is indicated 7
• For severe croup requiring repeat dosing, administer another dose of dexamethasone plus nebulized epinephrine regardless of timing of the initial dose 1
• Children should be reevaluated if symptoms do not improve within the expected timeframe (typically within 12-24 hours) 8