Introduction The aim of this open-label trial is to examine whether a single dose of dexamethasone is non-inferior to a 3-day course of prednisolone in the treatment of exacerbations of asthma in children who attend the Emergency Department (ED).

Methods Participants were identified on ED presentation, eligibility was confirmed and informed consent was obtained. Patients were randomised to receive either a stat dose of oral dexamethasone 0.3mg/kg (max 12mg) or prednisolone 1mg/kg/day (max 40mg) for 3 days. Otherwise standard treatment was administered.

Following discharge from the ED, patients were clinically reviewed on Day 4, and by telephone on Day 14. The primary outcome measure was the Pediatric Respiratory Assessment Measure (PRAM score) at Day 4. Secondary measures include relapse rate, requirement for more steroids, number of salbutamol therapies, and vomiting.

A sample size of 210 subjects will be sufficient to reject the null hypothesis - that the population means of both groups are equal with a probability of 0.9. The Type I error probability is 0.05.

Results 201 individual asthma exacerbations (101 prednisolone, 100 dexamethasone) have so far been enrolled. Demographic details and exacerbation severity are equal across both groups. We will complete enrolment in May 2012.

Conclusion The results of this randomised trial may have a significant impact on the management of acute asthma in children. At current rates we will complete recruitment in May 2012 and will present full reults at the conference.