Prednisolone versus dexamethasone in croup: a randomised equivalence trial.

BACKGROUND: Croup remains a common respiratory problem presenting to emergency departments. A single oral treatment of oral dexamethasone results in improved outcome. Prednisolone has similar pharmacokinetic properties and has a significant advantage in that it is commercially available in liquid preparations. OBJECTIVE: To ascertain whether a single oral dose of prednisolone was equivalent to a single oral dose of dexamethasone (matched for potency) in children with mild to moderate croup. DESIGN: A double blind, randomised, controlled equivalence trial. SETTING: Tertiary paediatric emergency department. Patients: 133 children aged 3 to 142 months presenting with mild to moderate croup. INTERVENTIONS: Children received either a single oral dose of dexamethasone 0.15 mg/kg or single oral dose of prednisolone 1 mg/kg. Outcome: The main outcome measure was unscheduled re-presentation to medical care as determined by telephone follow up at 7 to 10 days. Croup score, adrenaline (epinephrine) use, time spent in the emergency department, and duration of croup and viral symptoms were secondary outcome measures. RESULTS: Children treated with prednisolone were more likely to re-present: 19 of 65 children (29%) reattended medical care compared with 5 of 68 (7%) from the dexamethasone group. The confidence intervals around this 22% difference in outcome were 8% to 35%, outside the 0% to 7.5% range of equivalence. There were no significant differences in other outcome measures. CONCLUSION: A single oral dose of prednisolone is less effective than a single oral dose of dexamethasone in reducing unscheduled re-presentation to medical care in children with mild to moderate croup.