Background Although corticosteroids are commonly prescribed in the treatment of bronchiolitis, there is no evidence on the efficacy of these drugs in this disorder, We designed a randomised, double-blind, prospective study to assess the efficacy of dexamethasone in infants with bronchiolitis who require hospital management. Methods Infants younger than 12 months who had been admitted to hospital for an initial episode of wheezing, were randomly allocated intramuscular dexamethasone (1 mg/kg daily) or placebo, every 24 h for three doses. We excluded infants who were younger than 4 weeks, who required admission to the intensive care unit, or who had a history of congenital heart disease, mechanical ventilation, or supplemental oxygen use. We assessed infants on admission and every 12 h thereafter-vital signs were taken, severity of accessory muscle use and wheezing were measured by a clinical severity score, and pulse oximetry in room air was done. Our primary endpoints were the time to resolution of symptoms-defined as the number of assessments needed to reach oxygen saturation of more than 95% while receiving no supplemetal oxygen, an accessory muscle score of 0, a wheeze score of 0 or 1, and resumption of normal feeding-and duration of oxygen therapy. Follow-up assessments were made 10-14 days after discharge by telephone. We used a proportional-hazards model for our survival analysis. Findings 197 infants presented with bronchiolitis that required inpatient management. 75 were not enrolled (31 no consent, 28 no approach made, 16 transferred elsewhere). Of the 122 enrolled, four were excluded (clinical deterioration, diagnosis of cystic fibrosis, previous intubation, did not receive all study treatment). There were no differences between the dexamethasone (n=65) and placebo-treated infants in demographic factors, exposure to tobacco smoke, duration of illness, presence of respiratory syncytial virus (RSV) antigen, respiratory rate, or severity score. More dexamethasone-treated patients had an initial oxygen saturation of 95% or less (51 [79%] dexamethasone vs 31 [59%] placebo, p=0.02). There were no differences in duration of oxygen therapy (p=0.74) or time to resolution of symptoms (p=0.22). Stratification for presence of RSV antigen or family history of atopy did not affect the results. Interpretation Our findings do not support the use of dexamethasone in the treatment of bronchiolitis in infants.
