Acute effects of antacids on gastric juice components in duodenal ulcer patients

In 10 duodenal ulcer patients gastric juice was aspirated every 10 min for 20 min before and 200 min after sham feeding. One antacid tablet or placebo was given 80 min after the sham feeding. Analyses of the aspirates showed that antacids reduced mean hydrogen ion activity and pepsin concentration significantly for 40 and 60 min, respectively, and increased phospholipid concentration for 30 min, compared with placebo. Highest mean pH was 2.52. The percentage of pH readings at or above pH levels of 2, 3, and 4 during the 2 h period following antacid administration was 29, 10, and 2%, respectively. No significant differences between antacid and placebo were found regarding intragastric concentrations of bile acids and prostaglandin E2. When one antacid tablet was administered 80 min after a real meal, the effect on intragastric pH was similarly weak, but lasted slightly longer. Acid neutralization' alone can hardly explain the ulcer-healing effect of low-dose antacids. Antacid-induced increase in intragastric concentration of phospholipids is a new and potentially important observation.