Antacids and pepsin.

In a certain pH range, common antacids containing aluminium hydroxide gel have powerful adsorbent and precipitating effect on pepsin in human gastric juice, but there is no inactivation of pepsin apart from that produced by alteration of pH. In vivo, reduced pepsin concentration in aspirates from the stomach, after oral administration of aluminium hydroxide-containing antacids, may be due to precipitation of pepsin by the antacid within the stomach and the heavier, precipitated material not being withdrawn with the juice through the tube.