The objective of the study is to verify effects of nebulized 3% saline hypertonic solution (HS) in comparison to normal saline (NS) in addition to epinephrine in hospitalized children with bronchiolitis. Infants were randomly assigned either to receive every 6 hours nebulized NS (group I) or 3% HS (group II) in addition to epinephrine (1.5 mg) and to conventional treatment. The main endpoints of this study were the length of stay (LOS) in hospital and the clinical response score (CSS). Patients presented a significant decrease in CSS from the first through the third day of treatment, present in the first group but even more evident in the second group (p=0.0001). Comparison between group I and II data shows significant decrease in CSS in the 3% HS-treated patients both at the second (p<0.005) and at the third day of treatment (p<0.005). Infants in the NS control group had a mean LOS of 5.6±1.6 days, whereas children treated with 3% HS were discharged with a LOS of 4.9±1.3 days, reaching a significant decrease in stay (p<0.05). In hospitalized patients bronchiolitis nebulized 3% HS and epinephrine significantly decreased symptoms and LOS as compared to 0.9% NS and epinephrine.