Dexamethasone Dosing for a 2-Year-Old with Croup
For a 2-year-old child with croup, administer a single dose of oral dexamethasone 0.6 mg/kg (maximum 16 mg), which translates to approximately 7-8 mg for a typical 2-year-old weighing 12-13 kg. 1, 2
Standard Dosing Recommendation
The American Academy of Pediatrics recommends 0.6 mg/kg as the standard dose for pediatric croup, administered as a single dose orally, intramuscularly, or intravenously (maximum 16 mg). 1, 2
Oral administration is the preferred route when the child can tolerate it, as it is equally effective as intramuscular or intravenous routes while avoiding the pain of injection. 2
For a typical 2-year-old (12-13 kg), this calculates to 7-8 mg of dexamethasone. 2
Lower Dose Alternative
While the 0.6 mg/kg dose is the guideline-recommended standard, emerging evidence suggests a lower dose may be equally effective:
Dexamethasone 0.15 mg/kg may be as effective as 0.6 mg/kg for moderate to severe croup, with no significant differences in croup score reduction at 2,6, or 12 hours, return visits, or need for additional treatments. 3, 4
The lower dose (0.15 mg/kg) shows benefit as early as 30 minutes and is statistically significant by 30 minutes in mild to moderate croup. 5
However, the 0.6 mg/kg dose probably provides better symptom reduction at 24 hours compared to 0.15 mg/kg (moderate-certainty evidence). 4
Clinical Caveat on Dose Selection
Despite evidence supporting lower doses, current guidelines still recommend 0.6 mg/kg as the standard dose. 1, 2 The lower dose of 0.15 mg/kg may be considered for milder cases, but more research is needed to change the standard recommendation. 6, 4 When in doubt, use the guideline-recommended 0.6 mg/kg dose to ensure adequate treatment.
Timing and Duration of Action
Onset of action occurs as early as 30 minutes after administration. 1, 5
Duration of action is 24-72 hours, providing sustained relief without need for tapering or risk of significant adrenal suppression. 1, 2
Adjunctive Therapy for Severe Cases
If the child presents with moderate to severe croup (prominent stridor, significant retractions, respiratory distress):
Add nebulized epinephrine 0.5 mL/kg of 1:1000 solution (maximum 5 mL) while waiting for dexamethasone to take effect. 7, 1, 8, 2
Epinephrine provides immediate but short-term relief (minutes), while dexamethasone provides longer-lasting benefit (hours to days). 1
If racemic epinephrine is unavailable, substitute L-epinephrine (1:1000) at 0.5 mL/kg up to 5 mL. 8