Using a double-blind, placebo-controlled protocol, we evaluated the efficacy of nebulized albuterol in the treatment of infants aged 0 to 24 months who presented to the emergency department with wheezing. Twenty-five infants were randomly assigned to receive two identical treatments of either nebulized albuterol (0.15 mg/kg) or placebo (saline). Assessment after each treatment included a wheeze and retraction score, respiratory and heart rates, and pulse oximetry. After two treatments, there was a significant improvement in the wheeze scores (P less than 0.05) and total scores (P less than 0.05) of the albuterol group compared with the placebo group. After one treatment, there was an initial decrease in oxygen saturation in the albuterol group, which improved after the second treatment. There were no significant differences between the two groups in heart rate or respiratory rate. This study supports the use of nebulized albuterol in the treatment of wheezing infants in the emergency department.