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Peptic Ulcer Disease and GERD

For most of the twentieth century, doctors told patients with a burning stomach ulcer to relax, drink milk, and cut out spicy food — because everyone "knew" ulcers were caused by stress and acid. That comfortable story turned out to be mostly wrong, and the correction is one of the great detective stories of modern medicine. Peptic ulcer disease (PUD) and gastroesophageal reflux disease (GERD) are two of the most common conditions a clinician will ever manage, and they sit at the intersection of physiology, microbiology, and pharmacology. Understand them well and you understand a huge slice of everyday gastroenterology.

This page teaches you how stomach acid is made and controlled, how Helicobacter pylori and NSAIDs actually cause ulcers, how reflux disease differs from ulcers even though both "feel like heartburn," and how the modern drugs (PPIs, antibiotics) work. We will build the picture from mechanism up so the treatment choices feel obvious rather than memorised.

Learning Objectives​

  • Describe how gastric parietal cells secrete acid and how the three main stimulants (gastrin, histamine, acetylcholine) converge on the proton pump.
  • Explain the two dominant causes of peptic ulcers — H. pylori and NSAIDs — and how each breaks the mucosal defence.
  • Distinguish gastric from duodenal ulcers and both from GERD by pathophysiology, symptoms, and danger signs.
  • Recount how Marshall and Warren overturned the "stress causes ulcers" dogma and won the 2005 Nobel Prize.
  • Choose and justify appropriate diagnostic tests (urea breath test, endoscopy) and treatments (PPIs, H. pylori eradication, lifestyle change).
  • Recognise alarm features that mandate urgent endoscopy and referral.

Quick Answer​

Peptic ulcer disease is a break in the lining of the stomach or duodenum caused chiefly by Helicobacter pylori infection or NSAID use, both of which tip the balance between acid/pepsin attack and mucosal defence. GERD is the reflux of stomach contents into the oesophagus, causing heartburn and sometimes tissue damage, driven mainly by a weak or transiently relaxing lower oesophageal sphincter rather than by too much acid. Both are diagnosed clinically and confirmed with targeted tests — urea breath test or stool antigen for H. pylori, endoscopy when alarm features appear. Proton pump inhibitors (PPIs) are the cornerstone of treatment for both; ulcers additionally need H. pylori eradication (usually triple or quadruple therapy) or removal of the offending NSAID. Left untreated, ulcers can bleed or perforate, and long-standing GERD can cause Barrett's oesophagus, a precancerous change. The single most important historical lesson is that most ulcers are an infection — not a lifestyle failing — a truth proved by Barry Marshall and Robin Warren.

Where It Came From​

For decades the "balance theory" of ulcers reigned: no acid, no ulcer, so treatment meant neutralising or suppressing acid and calming the nervous stomach. Antacids, milk diets, vagotomy surgery, and later the H2-blocker cimetidine (Sir James Black, 1970s — itself a Nobel-winning breakthrough) all attacked acid. They healed ulcers, but the ulcers kept coming back, which should have been a clue that something was missing.

In 1979, an Australian pathologist named Robin Warren noticed curved bacteria colonising inflamed stomach biopsies — surprising, because the stomach was assumed too acidic to host bacteria. A young trainee, Barry Marshall, took up the puzzle. Together they cultured the organism (a lucky accident — a culture plate left over a long Easter weekend finally grew the fastidious bug) and proposed it caused gastritis and ulcers. The medical establishment was deeply sceptical.

Frustrated by the difficulty of proving causation ethically, Marshall in 1984 did something extraordinary: he drank a broth of the bacteria himself. Within days he developed gastritis, recovered the organism from his own stomach, and cured himself with antibiotics — a self-experiment that dramatically demonstrated Koch's postulates. The bacterium was named Helicobacter pylori. In 2005 Marshall and Warren received the Nobel Prize in Physiology or Medicine. Their work transformed a chronic relapsing surgical disease into something curable with a two-week course of pills — one of the clearest examples of how challenging dogma with evidence changes millions of lives.

Acid Physiology: The Machinery You Are Trying to Control​

To understand every drug and every ulcer, start with the parietal cell in the stomach's fundus and body. Its final common effector is the H+/K+ ATPase — the proton pump — which trades potassium in for hydrogen ions out, generating luminal acid a million times more concentrated than blood (pH can reach 1–2).

Three signals stimulate the pump, and they synergise:

  • Gastrin from antral G cells (released after meals, protein, and stomach distension).
  • Histamine from enterochromaffin-like (ECL) cells — the central amplifier; gastrin and vagal input both work largely through histamine.
  • Acetylcholine from vagal nerve endings (the "cephalic phase" — the reason thinking about food starts acid flowing).

Histamine acts on the H2 receptor, raising cyclic AMP; this is why H2-blockers (ranitidine, famotidine) reduce but do not abolish acid. Because all three pathways funnel into one pump, blocking the pump itself (PPIs) is the most complete acid suppression available — that single insight explains why PPIs outperform H2-blockers.

Defending against this acid is the mucosal barrier: a mucus-bicarbonate layer, tight epithelial junctions, rich mucosal blood flow, and prostaglandin-driven repair. Prostaglandins are the key defenders — and NSAIDs, which block cyclooxygenase (COX) and thus prostaglandin synthesis, strip that defence away. This is the mechanistic heart of NSAID ulcers.

Peptic Ulcer Disease: When the Balance Breaks​

An ulcer is a mucosal break deeper than 5 mm penetrating the muscularis mucosae — distinct from a shallow erosion. Two causes dominate:

1. H. pylori — a spiral, urease-producing, Gram-negative bacterium that colonises the mucus layer. Urease splits urea into ammonia, neutralising local acid and letting the bug survive; this reaction is exploited by the urea breath test. H. pylori causes chronic inflammation. Its location matters:

  • Antral-predominant infection increases gastrin, raises acid, and favours duodenal ulcers.
  • Body-predominant infection causes atrophy, lowers acid, and is linked to gastric ulcers and gastric cancer.

2. NSAIDs (and aspirin) — block protective prostaglandins, typically causing gastric ulcers, often silently until they bleed. Risk multiplies in the elderly, with high doses, with concurrent anticoagulants or steroids, or with co-existing H. pylori.

Rarer causes: the acid-hypersecreting Zollinger–Ellison syndrome (gastrinoma), stress ulcers in critical illness, and malignancy.

Symptom clue: classically, duodenal ulcer pain improves with food (acid is buffered) and wakes patients at night; gastric ulcer pain often worsens with food. In practice this overlap is unreliable — never diagnose ulcer type by symptoms alone.

Worked clinical example: A 58-year-old man on daily ibuprofen for arthritis presents with black, tarry stool (melaena) and light-headedness. He has no "classic" ulcer pain. This is a bleeding NSAID-induced gastric ulcer — a reminder that NSAID ulcers are frequently painless until they haemorrhage. He needs urgent endoscopy, IV PPI, resuscitation, and the NSAID stopped.

GERD: A Problem of the Sphincter, Not Just the Acid​

GERD is the reflux of gastric contents into the oesophagus causing troublesome symptoms or mucosal injury. The oesophagus, unlike the stomach, has no acid-proof lining, so even normal amounts of acid injure it.

The core defect is the lower oesophageal sphincter (LES) — either chronically weak or, more commonly, subject to transient LES relaxations. Contributing factors: hiatus hernia (the stomach slides above the diaphragm), obesity and raised intra-abdominal pressure, pregnancy, delayed gastric emptying, large fatty meals, and lying down after eating.

Symptoms: classic heartburn (retrosternal burning) and acid regurgitation, worse after meals and when supine. "Atypical" presentations matter for exams and clinic: chronic cough, hoarseness, dental erosion, and non-cardiac chest pain — always exclude cardiac causes first.

Complications of chronic reflux:

  • Reflux oesophagitis and peptic strictures (causing dysphagia).
  • Barrett's oesophagus — metaplasia of squamous to columnar epithelium, a precancerous change requiring surveillance because it raises risk of oesophageal adenocarcinoma.

Diagnosis: Match the Test to the Situation​

For young patients (typically under 55–60) with no alarm features and dyspepsia, guidelines favour a "test-and-treat" approach for H. pylori rather than immediate endoscopy.

  • Urea breath test and stool antigen test — non-invasive, good for diagnosis and confirming eradication. Both need PPIs stopped ~2 weeks and antibiotics/bismuth stopped ~4 weeks beforehand, or they give false negatives.
  • Endoscopy (OGD) with biopsy — the gold standard when alarm features are present; allows CLO/rapid urease testing, histology, and detection of malignancy.
  • Serology (antibodies) — cheap but cannot distinguish current from past infection; largely superseded.

ALARM features mandating urgent endoscopy (memorable as "ALARMS"): Anaemia (iron deficiency), Loss of weight, Anorexia, Recent onset progressive symptoms, Melaena/haematemesis, Swallowing difficulty (dysphagia). New dyspepsia over age 55 also warrants scope. These features raise concern for bleeding ulcer or cancer.

Treatment: From Neutralising Acid to Curing Infection​

Proton pump inhibitors (omeprazole, lansoprazole, pantoprazole, esomeprazole) are first-line for both PUD and GERD. They irreversibly bind the proton pump; taken 30–60 minutes before breakfast so peak drug meets newly activated pumps. They heal ulcers and oesophagitis reliably.

H. pylori eradication — if the bug is present, healing without eradication just invites relapse. Standard regimens (choice depends on local resistance and penicillin allergy):

  • Triple therapy: a PPI + clarithromycin + amoxicillin (or metronidazole) for 7–14 days.
  • Bismuth quadruple therapy: PPI + bismuth + tetracycline + metronidazole — preferred where clarithromycin resistance is high. Always confirm eradication with a breath or stool test at least 4 weeks after finishing, especially after a complicated ulcer.

NSAID ulcers: stop the NSAID if possible; treat with a PPI. If NSAIDs are unavoidable, co-prescribe a PPI for gastroprotection and consider a COX-2 selective agent (gentler on the stomach but with cardiovascular trade-offs).

GERD stepwise: weight loss, elevate the head of the bed, avoid late meals, alcohol, and trigger foods; antacids/alginates for mild symptoms; PPIs for troublesome or erosive disease. Anti-reflux surgery (fundoplication) is reserved for selected patients with proven reflux who fail or cannot tolerate medical therapy.

H2-blockers (famotidine) remain useful add-ons, particularly for nocturnal acid breakthrough.

Real-World Applications​

  • Primary care dyspepsia: most young patients with heartburn are managed with test-and-treat and lifestyle advice, avoiding unnecessary endoscopy — an evidence-based, cost-effective pathway.
  • Preventing GI bleeds: identifying high-risk NSAID users and co-prescribing PPIs prevents thousands of hospital admissions for upper GI haemorrhage each year.
  • Cancer prevention: eradicating H. pylori reduces gastric cancer risk; Barrett's surveillance catches oesophageal adenocarcinoma early.
  • Everyday relevance: simple habits — not eating within 3 hours of bed, losing weight, moderating alcohol — meaningfully cut reflux symptoms without any medication.

Common Mistakes​

  1. "Ulcers are caused by stress and spicy food." Wrong for the vast majority — H. pylori and NSAIDs cause most ulcers. Stress and diet can aggravate symptoms but do not create the mucosal break. Correction: test for and treat the actual cause.
  2. Assuming all "heartburn" is GERD. Retrosternal pain can be cardiac (angina, MI), and epigastric pain can be an ulcer, gallstones, or pancreatitis. Correction: exclude cardiac causes and screen for alarm features before labelling it reflux.
  3. Testing for H. pylori while the patient is on a PPI. PPIs suppress the organism and cause false-negative breath and stool tests. Correction: stop the PPI ~2 weeks before testing (and antibiotics/bismuth 4 weeks).
  4. Healing an ulcer with a PPI but never eradicating H. pylori. The ulcer relapses. Correction: always test for and eradicate the infection, then confirm cure.
  5. Ignoring painless bleeding in NSAID users. NSAID ulcers are often silent until they haemorrhage. Correction: have a low threshold for endoscopy in anaemic or bleeding NSAID users.

Comparison and Connections​

FeatureDuodenal ulcerGastric ulcerGERD
Main causeH. pylori (antral)NSAIDs, H. pylori (body)Weak/transient LES relaxation
Acid levelOften highNormal or lowNormal (oesophagus intolerant)
Pain and foodRelieved by food, night painOften worse with foodWorse after meals, lying down
Cancer riskVery lowMust biopsy to exclude cancerBarrett's then adenocarcinoma
Key testUrea breath / stool antigenEndoscopy + biopsyClinical; endoscopy if alarm
First-line drugPPI + eradicationPPI (+ stop NSAID/eradicate)PPI + lifestyle

Connections: acid physiology links to Pharmacology (PPIs, H2-blockers, NSAIDs and COX). H. pylori connects to Microbiology. Upper GI bleeding is a core Emergency Medicine topic, and the underlying tissue changes belong to Pathology.

Practice Questions​

Recall​

Q: Name the enzyme H. pylori produces that both aids its survival and forms the basis of a common diagnostic test. A: Urease — it splits urea into ammonia and CO2, neutralising local acid; the labelled-urea breath test detects the released CO2.

Understanding​

Q: Why do proton pump inhibitors suppress acid more completely than H2-blockers? A: Acid secretion is driven by three stimulants (gastrin, histamine, acetylcholine) that all converge on the H+/K+ ATPase proton pump. H2-blockers only block the histamine pathway, so other stimuli still drive some acid. PPIs block the final common effector — the pump itself — producing more complete and durable suppression.

Application​

Q: A 32-year-old with epigastric pain relieved by food, no alarm features, not on NSAIDs. Outline your approach. A: This is uninvestigated dyspepsia in a young patient without alarm features — use "test-and-treat": non-invasive H. pylori test (breath/stool). If positive, give eradication therapy; if negative or symptoms persist, trial a PPI and review. Endoscopy is not first-line here.

Analysis​

Q: A patient completed triple therapy but a breath test done 5 days later is negative. Can you conclude eradication succeeded? Explain. A: No. The test was done too soon and possibly while still on/just off a PPI, both of which suppress the organism and cause false negatives. Confirmation testing must be at least 4 weeks after antibiotics and ~2 weeks off PPIs. Repeat correctly before concluding cure.

FAQ​

Is H. pylori contagious? It spreads person-to-person, likely oral-oral and faecal-oral, often acquired in childhood and in crowded conditions. Most infected people never develop ulcers, but those who do can be cured with antibiotics.

Can stress and diet really cause ulcers? They are not the primary cause. However, severe physiological stress (major illness, burns, ICU) can cause "stress ulcers," and certain foods, alcohol, and smoking can worsen symptoms and impair healing. The main culprits remain H. pylori and NSAIDs.

Are PPIs safe long-term? For most people, yes, and the benefits usually outweigh risks. Long-term use has been associated with modestly increased risks (certain infections, low magnesium, possible fracture risk, B12 issues) — so use the lowest effective dose and review the need periodically. This is a judgement call for the prescriber.

What is the difference between an erosion and an ulcer? Depth. An erosion is superficial and does not breach the muscularis mucosae; an ulcer is deeper and can reach blood vessels, hence the risk of significant bleeding or perforation.

How worried should I be about Barrett's oesophagus? Barrett's is a change in the oesophageal lining from chronic reflux and is precancerous, but the majority of people with Barrett's never develop cancer. It warrants endoscopic surveillance so any early change is caught and treated. Controlling reflux with PPIs and lifestyle is important.

Why do some ulcers cause no pain at all? NSAIDs blunt the inflammatory/pain response and reduce protective prostaglandins, so ulcers can develop silently and present first as bleeding — one reason painless NSAID ulcers are dangerous.

Quick Revision​

  • Acid is made by parietal cells via the H+/K+ proton pump, stimulated by gastrin, histamine (H2), and acetylcholine.
  • PPIs block the pump — most complete acid suppression; take before breakfast.
  • Most ulcers: H. pylori or NSAIDs. Duodenal ulcer = relieved by food; gastric ulcer = worse with food (unreliable in practice).
  • H. pylori: urease-positive; diagnose with urea breath/stool antigen (off PPIs 2 weeks); cure with triple/quadruple therapy; confirm eradication.
  • GERD is a sphincter problem, not just acid; risk factors include obesity and hiatus hernia; complication path is oesophagitis then Barrett's then adenocarcinoma.
  • ALARMS (anaemia, weight loss, anorexia, recent progressive, melaena/haematemesis, swallowing difficulty) or age over 55 = urgent endoscopy.
  • Marshall and Warren proved H. pylori causes ulcers; Nobel Prize 2005.

Prerequisites​

Next Topics​

  • General Surgery — surgical management of perforation and fundoplication
  • Oncology — gastric and oesophageal cancer