What is the recommended steroid dosage for treating croup?

Steroid Dosage for Croup

For children with croup, administer dexamethasone 0.15 mg/kg as a single dose (maximum 3 mg), which is equally effective as higher doses and minimizes potential adverse effects. 1, 2

Recommended Dosing Regimen

First-Line Treatment: Dexamethasone

• Dose: 0.15 mg/kg as a single dose (maximum 3 mg) 1, 2
• Route: Oral or intramuscular—both routes are equally effective 3
• Timing: Symptoms typically improve within 2 hours, with maximal effect by 6-12 hours 1, 4

Evidence Supporting Lower Dose (0.15 mg/kg)

• Multiple RCTs demonstrate that 0.15 mg/kg dexamethasone is as effective as 0.3 mg/kg or 0.6 mg/kg for:
  • Reduction in croup scores at 2,6, and 12 hours 2, 4
  • Duration of hospitalization 2
  • Need for additional treatments including nebulized epinephrine 4
  • Return visits or readmissions 4
• High-certainty evidence shows no difference between 0.15 mg/kg and 0.60 mg/kg at 2 hours post-treatment 4
• The only potential advantage of 0.60 mg/kg over 0.15 mg/kg is a modest reduction in croup severity at 24 hours, but this does not translate to clinically meaningful differences in outcomes 4

Alternative Steroid Options

Nebulized Budesonide

• Dose: 2 mg via nebulization 5
• Efficacy: Equivalent to oral dexamethasone 0.15 mg/kg for mild to moderate croup 6, 5
• Consideration: Oral dexamethasone and nebulized corticosteroids are equally effective according to European Respiratory Society guidelines 6

Prednisolone

• Comparison to dexamethasone: High-certainty evidence shows little to no difference in croup score reduction at 2 hours 4
• Disadvantage: Dexamethasone reduces return visits/readmissions by approximately 45% compared to prednisolone (RR 0.55) 4
• Severe croup requiring intubation: Prednisolone 1 mg/kg every 12 hours decreases duration of intubation 5

Route of Administration

Oral vs. Intramuscular

• No significant difference in clinical outcomes between oral and IM dexamethasone 0.6 mg/kg 3
• Oral route is preferred when feasible due to:
  • Non-invasive administration 3
  • Equal efficacy to IM route 3
  • Patient/parent preference
• IM route reserved for children unable to tolerate oral medication 3

Clinical Pitfalls and Caveats

Common Errors to Avoid

• Do not use higher doses unnecessarily: The traditional 0.6 mg/kg dose offers no advantage over 0.15 mg/kg for most outcomes 1, 2, 4
• Do not use inhaled corticosteroids via spacer: Hand-held inhalers with spacer devices have NOT been shown effective for croup, unlike nebulized corticosteroids 6
• Do not withhold steroids: Glucocorticoids are the mainstay of croup treatment with benefits clearly outweighing risks 5, 4

Safety Considerations

• Single or short courses have minimal risks 5
• Only significant potential adverse effect: Increased risk of severe varicella infection in exposed children 5
• No major adverse effects reported with short courses of nebulized budesonide 5

Adjunctive Therapy

• Nebulized epinephrine (0.5 ml/kg of 1:1000 solution): Used for severe croup to avoid intubation or stabilize prior to transfer, but effect is short-lived (1-2 hours) 6
• Should not be used for outpatient management or in children about to be discharged 6

Expected Clinical Response

Timeline for Improvement

• 2 hours: Initial symptom reduction evident 1, 4
• 6-8 hours: Median time to achieve croup score ≤2 1
• 12 hours: Maximal effect typically achieved 4
• Re-evaluation: If no improvement within expected timeframe, reassess for alternative diagnoses or complications 4