Clinical evaluation and prolonged esophageal pH monitoring were performed before and during treatment with cisapride (0.3 mg/kg t.i.d.) for 1 month in 19 children with reflux-associated bronchopulmonary disease. Results (mean +/- SEM) show that cisapride significantly decreases the frequency of long duration (greater than 5 min) reflux episodes (from 9.7 +/- 0.7 to 5.7 +/- 1.2), the percentage of total time pH was less than 4 (from 15.9 +/- 2.5 to 7.7 +/- 1.1%), the percentage of time pH was less than 4 at night (from 18.0 +/- 3.9 to 4.9 +/- 1.5%), the duration of the longest reflux episodes (from 44.5 +/- 6.4 to 19.7 +/- 2.7 min), as well as the duration of reflux at night (from 100.1 +/- 28.0 to 28.2 +/- 10.1 min). The frequency of reflux episodes, however, remains unaffected by cisapride. Cough fits at night disappeared completely in 12 out of 13 children. We conclude that cisapride given for 1 month significantly decreased gastroesophageal reflux as well as cough episodes at night.