How does an ulcer form and how does it heal?
An ulcer is a wound that goes through the lining of the stomach or duodenum, often because of the bacterium H. pylori or anti-inflammatory drugs. At the end of trials, at least 67% of stomach ulcers had healed with a PPI acid reducer, never more than 39% with a placebo (Salas, 2002).
Schematic drawings, not to scale, no patient photos. Dotted lines are estimates between measured points.
How does an ulcer dig in, then close up?
The lining in cross-section, layer by layer. Choose what happens; tap a label to find out what it is.
Who attacks, who protects?
Sources: frequency and symptoms (Aro, 2006; Sung, 2009); healing (Salas, 2002; Zhang, 2019); recurrence (Ford, 2016, to be verified); protection (Scally, 2018); complications (Lau, 2011; Buck, 2013). These are group averages: they do not predict any individual case.
Which ulcer signs need emergency care?
Four signs to know. Tap one to see what may be happening in the belly. With any of them, call emergency services without waiting.
With these signs Call emergency services. Do not wait to see if it passes. Say which medicines you take.
Sources: complications (Lau, 2011, 93 studies); delay before surgery (Buck, 2013; Boyd-Carson, 2020); list of signs to be verified against a public health source, such as the NHS.
Which anti-inflammatories harm the stomach most?
The risk of complications in the upper digestive tract, compared with people who do not take them. Tap a row for details.
How to read this: "× 2" means 2 times as many complications as without an anti-inflammatory, not a 2% risk. The white line shows the margin of the estimate.
Source: Castellsague, 2012, 28 observational studies: they show a link, without proving the cause on their own. These figures do not replace a doctor's advice, especially if the treatment also protects against something else.
Frequently asked questions about ulcers
How long does an ulcer take to heal?
Usually a few weeks of treatment (timing to be verified). At the end of trials, at least 67% of stomach ulcers had healed with a PPI, at most 39% with a placebo (Salas, 2002). The cause must also be treated, or the ulcer may come back.
Can you have an ulcer without pain?
Yes. Of the 41 ulcers found among 1,001 Swedish adults, 8 caused no symptoms, or about 20% (Aro, 2006, our calculation). It may then show up through a complication.
Does stress cause ulcers?
It seems to contribute. In a Danish cohort of 3,379 adults, the most stressed people had them twice as often (3.5% versus 1.6%, adjusted odds ratio 2.2; Levenstein, 2015). This is an observed link, not proof of cause, and stress does not replace the bacterium or medicines as an explanation.
What are the emergency signs?
Black stools, vomited blood, sudden severe pain, faintness with pallor: call emergency services (list to be verified against a public health source).
Can an ulcer come back?
Yes, especially if the cause remains. Without the bacterium, a duodenal ulcer comes back much less often: 12.9% versus 64.4% without treatment (Ford, 2016, to be verified).
True or false?
An ulcer always hurts.
False. About 1 ulcer in 5 caused no symptoms in a Swedish study: 8 of 41 (Aro, 2006, our calculation).
Chili peppers cause ulcers.
False, as far as the little evidence goes: in 18 volunteers, 20 g of chili reduced the lesions later caused by aspirin (Yeoh, 1995). A small study in healthy people: it says nothing about an ulcer already there.
Not all anti-inflammatories carry the same risk for the stomach.
True. Risk multiplied by 1.45 with celecoxib and 7.43 with piroxicam (Castellsague, 2012).
This page as text
The same information as the charts, to read without animation: for each chart, the values at the main moments, then the notes with their level of evidence.
How many stomach ulcers have healed by the end of a trial?
At least 67% with a PPI, at most 39% with a placebo (Salas, 2002). Dotted lines: a straight line between the start and the measured point, not a measurement. Trial length, 4 to 8 weeks, to be verified.
| Time | PPI: at least 67% (dotted) | Placebo: at most 39% (dotted) | What happens |
|---|---|---|---|
| Start | 0 | 0 | Week 0: start of treatment |
| 4 weeks | 34 | 20 | Week 4: estimate between the start and the end of the trial |
| 8 weeks | 67 | 39 | Week 8: end of the trial, measured point |
Key points
- PPI versus ranitidine (Throughout, Shown in humans)
At 4 weeks, stomach ulcers heal more often with a PPI: relative risk 1.33 (1.24 to 1.42). Source: Salas et al., BMC Gastroenterol, 2002 - What about the duodenum? (Throughout, Shown in humans)
All PPIs do better at 4 weeks than H2 blockers and placebo, with no difference among them (62 trials, 10,339 participants). Source: Zhang et al., Front Pharmacol, 2019 - How to read these lines (Throughout, Hypothesis)
Only the end point comes from the trials. A wound does not necessarily close at a steady speed.
After H. pylori is eliminated, does a duodenal ulcer come back?
Much less often: 12.9% versus 64.4% without treatment (Ford, 2016, to be verified, very low quality evidence). The timing of the measurement is not confirmed, so the 12-month axis is still to be verified. Dotted lines: a straight line, not a measurement.
| Time | No treatment: 64.4% (to be verified) (dotted) | Bacterium eliminated: 12.9% (to be verified) (dotted) | What happens |
|---|---|---|---|
| End of treatment | 0 | 0 | Month 0: end of treatment |
| 6 months | 32 | 6 | Month 6: estimate between the start and the last measurement |
| 12 months | 64 | 13 | Month 12: last measurement, timing to be verified |
Key points
- Stomach ulcers (Throughout, Shown in humans)
Eliminating it also reduces the return of the ulcer: relative risk 0.31 (12 trials, 1,476 patients). Source: Ford et al., "Eradication therapy for peptic ulcer disease in Helicobacter pylori-positive people," Cochrane Database Syst Rev, 2016 - Caution about this figure (Throughout, Hypothesis)
These 2 values were read in excerpts; the full article could not be read. They are still to be verified. Source: Ford et al., "Eradication therapy for peptic ulcer disease in Helicobacter pylori-positive people," Cochrane Database Syst Rev, 2016
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