The stomach guards itself from its own acid with a coat of mucus. Wreck that coat and acid digs in. First comes inflammation, called gastritis. Then comes an open sore, an ulcer. H. pylori bacteria and NSAIDs do most of the wrecking. So how do you tell a gastric ulcer from a duodenal one? By when the pain hits, compared with eating. Press "Just ate" and watch.
Stomach & duodenum
Acid pools in the stomach. The duodenum is the first stretch of small intestine just past it. Watch where the lining breaks down.
Pick a condition to begin.
Pick a conditiongastritis · gastric · duodenal
Pain level—
What's happening
The pain-timing rule. A Gastric ulcer means pain that Gets worse when you eat, since food brings more acid and more churning onto the sore. A Duodenal ulcer means pain when the stomach is empty, often at night, and eating eases it. The #1 cause of both is H. pylori. NSAIDs, aspirin, and steroids come next.