Acid and gastric ulcer pain.

We have shown previously that acid is one factor, although not the only one, in the pathogenesis of duodenal ulcer pain. In the present study patients with gastric ulcer were endoscoped without sedation or premedication. Under direct vision the ulcer craters were infused sequentially with 0.1 N HCl and normal saline, the sequence of infusion being randomized and double blind. Typical ulcer pain occurred in seven of 19 patients during acid infusion compared with one with saline (p = 0.023). Two patients who developed pain on acid were rechallenged after their pain disappeared, and typical pain recurred in both. Acid therefore has a definite role in the pathogenesis of gastric ulcer pain.