Participants were randomized based on results of a 24 hour pH study, which determined the average percent time the distal esophagus was exposed to a pH of less than than 4. Subjects with a positive pH result were randomized to esomeprazole or randomized to budesonide, if there was a negative pH result. Studies were interpreted by a single gastroenterologist experienced in reading esophageal pH studies. The percent time the pH monitor detected a pH less than 4 was recorded and an esophageal pH of less than 4 for 4% or greater of the study time was considered abnormal. Note: pH is a measure of acidity or alkalinity (lower numbers are more acid, higher numbers are more alkaline).