- Objective: To evaluate the effect of inhaled dexamethasone on hospitalization for respiratory syncytial virus (RSV) bronchiolitis. Study design: A double-blind, placebo-controlled study compared nebulization of dexamethasone versus nebulization of 0.9% saline. Both groups were treated with epinephrine nebulizations. Follow-up continued for 3 mo. Patients and methods: Sixty-one infants with bronchiolitis aged 3 to 12 mo were included. They were randomly allocated to nebulizations with 0.25 mg dexamethasone every 6 h (group 1) or an equivalent amount of normal saline (group 2). Results: No statistically significant differences with respect to clinical score, oxygen saturation, or IV fluid requirement between the groups were noted. Using Kaplan-Meyer's method, the cumulative proportion of in-hospital stay was significantly lower in group 1 compared with group 2, mainly in days 5 and 6 post-hospitalization (p<0.038). A subgroup of prematurely born children in group 1 had a shorter hospitalization period (6.5±1.7 d) compared with group 2 children (9.1±1.9) (p<0.018). Follow-up revealed similar wheeze and hospitalization rates in the two groups. Conclusion: Inhaled dexamethasone may reduce the length of hospitalization among infants with acute viral bronchiolitis, especially among those born prematurely.