Treatment of Classical Croup
The most appropriate initial treatment is C. Dexamethasone 0.6 mg/kg, which should be administered to all children with croup regardless of severity. 1
First-Line Treatment: Corticosteroids
- Oral dexamethasone 0.15-0.6 mg/kg (maximum 10-12 mg) as a single dose is the gold standard first-line treatment for all cases of croup, regardless of severity. 1, 2
- The dose range of 0.15-0.6 mg/kg is equally effective—studies demonstrate no difference in outcomes between these doses for moderate to severe croup. 3
- Dexamethasone begins working much earlier than previously thought, with statistically significant benefit evident by 30 minutes (not the 4-6 hours previously suggested). 4
- Oral administration is preferred over intramuscular or intravenous routes when the child can tolerate it. 5
When to Add Nebulized Epinephrine
- Reserve nebulized epinephrine (racemic or L-epinephrine) for moderate to severe croup with stridor at rest or significant respiratory distress. 1, 2
- Dosing: 0.5 mL/kg of 1:1000 solution (maximum 5 mL) nebulized. 1
- Critical pitfall: Epinephrine provides rapid but temporary relief lasting only 1-2 hours, requiring mandatory observation for at least 2 hours after the last dose to monitor for rebound symptoms. 1, 2
- Never discharge a patient within 2 hours of epinephrine administration. 2
Why Not the Other Options?
- Cool mist (Option A) has no proven benefit—current evidence shows no symptom improvement from humidified or cold air therapy. 2, 5
- Prednisolone 0.2 mg/kg (Option B) is underdosed—the effective prednisolone dose is 1-2 mg/kg (maximum 40 mg), not 0.2 mg/kg. 6, 7
- Racemic epinephrine (Option D) is not first-line—it should be reserved for moderate to severe cases after corticosteroids are given, not as initial monotherapy. 1, 2
Treatment Algorithm by Severity
Mild croup:
- Oral dexamethasone 0.15-0.6 mg/kg alone is sufficient. 1
Moderate to severe croup (stridor at rest, respiratory distress):
- Oral dexamethasone 0.15-0.6 mg/kg PLUS nebulized epinephrine 0.5 mL/kg of 1:1000 solution. 1, 2
- Observe for minimum 2 hours after last epinephrine dose. 2
Hospitalization Criteria
- Need for ≥3 doses of nebulized epinephrine (the "3 is the new 2" approach reduces admissions by 37% without safety concerns). 1, 2
- Oxygen saturation <92%. 1
- Age <18 months. 1
- Respiratory rate >70 breaths/min. 1
- Persistent respiratory distress. 1
Critical Pitfalls to Avoid
- Never use epinephrine in outpatient settings where immediate return is not feasible—rebound symptoms can occur after the 1-2 hour effect wears off. 2
- Never admit after only 1-2 doses of epinephrine when a third dose could be safely given in the emergency department—this unnecessarily increases hospitalization rates. 1
- Never rely on cool mist therapy as definitive treatment—it lacks evidence of benefit. 2, 5
- Never use antibiotics routinely—croup is viral in etiology. 1