The effect of oral metoclopramide (15 mg), AlMgOH (30 ml), and placebo on the cumulative duration of gastroesophageal reflux induced by a protein-rich meal was compared in 15 patients with reflux esophagitis. Oral metoclopramide was found to be more effective than AlMgOH in reducing the cumulative duration of reflux after placebo over a 3-hr period. The same dose of oral metoclopramide increased resting lower esophageal sphincter pressures in all 15 patients for at least 1 hr and prevented gastroesophageal reflux after an intragastric acid load (300 ml of O.1 N HCl) in 8 of 10 of these patients. Oral metoclopramide, however, failed to increase the amplitude of esophageal contractions and acid clearing of the distal esophagus. These findings suggest that oral metoclopramide in the dose of 15 mg may be potentially valuable in the management of reflux esophagitis.