Croup Treatment: Corticosteroid Therapy
For a child with croup, administer a single dose of oral dexamethasone 0.15-0.6 mg/kg (maximum 10-12 mg) as first-line therapy, NOT prednisolone, as prednisolone has been shown to result in significantly higher rates of unscheduled return to medical care. 1, 2
Why Dexamethasone Over Prednisolone
Prednisolone 1 mg/kg is inferior to dexamethasone for croup management, with a randomized controlled trial demonstrating that 29% of children treated with prednisolone re-presented to medical care compared to only 7% in the dexamethasone group—a clinically significant 22% difference. 2
While prednisolone has similar pharmacokinetic properties and the advantage of commercial liquid preparations, this convenience does not outweigh its reduced clinical effectiveness in preventing symptom recurrence. 2
Recommended Dexamethasone Dosing Algorithm
For all severities of croup:
- Oral dexamethasone 0.15-0.6 mg/kg as a single dose (maximum 10-12 mg) is the standard of care. 1, 3, 4
Dose selection by severity:
- Mild croup: Consider the lower end of the dosing range (0.15-0.3 mg/kg), though evidence supports treating all croup patients who seek medical care regardless of severity. 3
- Moderate-to-severe croup: Use 0.6 mg/kg, which has the strongest evidence base and has become standard practice. 3, 5
When to Add Nebulized Epinephrine
Add nebulized epinephrine (0.5 ml/kg of 1:1000 solution, maximum 5 ml) only for moderate-to-severe croup characterized by stridor at rest or significant respiratory distress. 1, 6
Epinephrine provides rapid but temporary relief lasting only 1-2 hours, requiring mandatory observation for at least 2 hours after each dose to monitor for rebound symptoms. 1, 6
Never use nebulized epinephrine in outpatient settings where the child will be discharged shortly, as rebound airway obstruction can occur. 1, 6
Alternative Corticosteroid Options
Nebulized budesonide 2 mg is equally effective as oral dexamethasone and may be used when oral administration is not feasible (e.g., vomiting, severe respiratory distress). 1, 7
Intramuscular dexamethasone 0.6 mg/kg is reserved for patients unable to tolerate oral medication due to vomiting or severe respiratory distress. 3, 5
Duration of Therapy
A single dose is sufficient—there is no evidence supporting multi-day courses (such as the 3-day prednisolone regimen mentioned in your question). 1, 3, 4
The onset of dexamethasone action is approximately 6 hours, which is why nebulized epinephrine may be needed as a bridge in severe cases. 5
Hospitalization Criteria
Consider admission when:
- Three or more doses of nebulized epinephrine are required (implementing "3 is the new 2" reduces admissions by 37% without increasing adverse outcomes). 1, 6
- Oxygen saturation <92% on room air. 1, 6
- Age <18 months with severe symptoms. 1, 6
- Respiratory rate >70 breaths/min. 1
- Family unable to provide appropriate observation at home. 6
Critical Pitfalls to Avoid
- Do not use prednisolone instead of dexamethasone—the evidence clearly demonstrates inferior outcomes. 2
- Do not discharge within 2 hours of nebulized epinephrine administration—rebound symptoms are a real risk. 1, 6
- Do not give over-the-counter cough medicines—they provide no benefit and may cause harm. 1
- Do not use antibiotics routinely—croup is viral and antibiotics are ineffective. 1
- Do not rely on humidified or cold air therapy—current evidence shows no benefit. 6, 4
Discharge Instructions
Discharge is appropriate when:
- At least 2 hours have elapsed since last epinephrine dose without rebound symptoms. 6
- Oxygen saturation >92% on room air. 6
- Minimal or no respiratory distress present. 1
- Reliable caregiver able to monitor and return if worsening. 6
Instruct families to: