Dexamethasone for Croup: Oral Administration Preferred
For children with croup, administer a single oral dose of dexamethasone 0.6 mg/kg (maximum 16 mg) as the first-line treatment. 1, 2
Route of Administration
- Oral administration (syrup or tablet) is the preferred route when the child can tolerate it, as it is equally effective as intramuscular or intravenous routes and avoids the pain of injection. 1, 2
- All three routes (oral, IM, IV) demonstrate equal efficacy for croup treatment. 1, 2
- Reserve intramuscular dexamethasone only for children who are vomiting or in severe respiratory distress and unable to tolerate oral medication. 3
Dosing Specifications
- Standard dose: 0.6 mg/kg (maximum 16 mg) administered as a single dose. 1, 2
- For a typical 2-year-old weighing 12-13 kg, this translates to approximately 7-8 mg. 2
- For a child weighing 38 kg, the calculated dose would be 22.8 mg, but it is capped at the maximum of 16 mg (4 mL volume). 1
Lower Dose Evidence
While research demonstrates that lower doses (0.15 mg/kg) can be effective 4, 5, 6, the guideline-recommended dose remains 0.6 mg/kg because it provides consistent benefit across all severity levels without significant adverse effects. 1, 2 The higher dose ensures adequate treatment without concern for underdosing, particularly since single-dose dexamethasone does not require tapering and does not cause significant adrenal suppression. 1, 2
Clinical Onset and Duration
- Onset of action occurs as early as 30 minutes after administration, with statistically significant improvement demonstrated by this timepoint. 1, 2, 4
- Duration of action is 24-72 hours, providing sustained relief. 1, 2
- No tapering is required for the single-dose regimen. 1, 2
Management of Moderate to Severe Croup
For children with prominent stridor, significant retractions, and respiratory distress:
- Administer nebulized epinephrine (0.5 mL/kg of 1:1000 solution, maximum 5 mL) in conjunction with dexamethasone. 1, 2, 7
- Epinephrine provides immediate but short-term symptom improvement (minutes), while dexamethasone provides longer-lasting relief (hours to days). 1, 2
- If racemic epinephrine is unavailable, L-epinephrine (1:1000) can be substituted at the same dosage. 7
Repeat Dosing for Severe Cases
- For severe croup with persistent symptoms, administer a repeat dose of dexamethasone plus nebulized epinephrine regardless of the timing of the initial dose. 1, 2
Critical Caveats
- Do not use nebulized corticosteroids from hand-held inhalers with spacers—they are ineffective for croup. 1
- Dexamethasone is specifically indicated for croup (laryngotracheobronchitis) and provides no benefit for pertussis-associated cough or non-specific chronic cough. 8, 1
- The characteristic "seal-like barking cough" is the classic recognizable feature of croup that distinguishes it from other respiratory conditions. 2