Pathophysiology: Acid Reflux and Lower Oesophageal Sphincter Dysfunction
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Acid reflux (Gastro-oesophageal reflux disease, GORD): Occurs when gastric contents flow back into the oesophagus.
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The lower oesophageal sphincter (LES) is a muscular ring at the junction of the oesophagus and stomach. It normally prevents reflux.
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Dysfunction: If the LES is weak, relaxes inappropriately, or is disrupted (e.g., by hiatal hernia), stomach acid can enter the oesophagus.
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Acid exposure damages the oesophageal lining, causing symptoms and, in severe cases, complications like oesophagitis, strictures, or Barrett’s oesophagus.
Clinical Features
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Heartburn: Burning sensation rising from the stomach or lower chest towards the neck.
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Regurgitation: Sensation of acid or food coming back into the throat or mouth.
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Chest pain: Retrosternal discomfort, may mimic cardiac pain but usually related to meals or lying down.
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Other features: sour/bitter taste, bloating, dysphagia (difficulty swallowing), chronic cough, hoarseness.
Diagnosis
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pH monitoring: 24-hour oesophageal pH study detects episodes and severity of acid reflux.
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Endoscopy: Visualises mucosal damage (oesophagitis, ulcers, Barrett’s changes). Indicated for red-flag symptoms (e.g., dysphagia, weight loss, GI bleeding, anaemia) or failed empirical therapy.
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Other: Oesophageal manometry (for motility disorders), barium swallow (rarely used now).
Pharmacological Management
| Drug Class | Examples | Mechanism / Use |
|---|---|---|
| Antacids | Gaviscon, Rennie | Neutralise stomach acid; rapid symptom relief |
| PPIs | Omeprazole, lansoprazole | Inhibit gastric proton pumps (H⁺/K⁺-ATPase); most effective for healing and symptom relief; first-line for moderate-severe GORD or oesophagitis |
| H2 blockers | Ranitidine (now less used), famotidine | Block histamine H2 receptors on gastric parietal cells; reduce acid secretion; alternative if PPIs not tolerated |
| Prokinetics | Domperidone, metoclopramide (short-term) | Enhance gastric emptying and LES tone; limited role due to side effects; not routinely used |
Lifestyle Modification and Dietary Interventions
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Weight loss if overweight.
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Elevate head of bed and avoid lying down soon after eating.
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Reduce meal size and avoid eating late at night.
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Avoid triggers: spicy/fatty foods, chocolate, caffeine, alcohol, citrus, peppermint.
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Smoking cessation and moderation of alcohol intake.
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Tight clothing around the waist should be avoided.
Mnemonic:
“WEEATS” — Weight loss, Elevate bed, Eat less, Avoid triggers, Tobacco stop, Smaller meals
UK NICE Guidelines on GORD Management
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Offer a trial of a PPI for 4–8 weeks for typical symptoms (heartburn, regurgitation).
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If symptoms persist, consider double-dose PPI or alternative diagnosis.
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Endoscopy if red-flag features (dysphagia, weight loss, anaemia, GI bleeding), persistent symptoms, or for those over 55 with new symptoms.
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Advise lifestyle and dietary changes alongside medication.
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For maintenance, use the lowest effective PPI dose or on-demand therapy.
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Refer for surgical assessment (e.g., fundoplication) if refractory symptoms or complications.
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Avoid long-term use of prokinetics and H2 blockers unless PPIs are unsuitable.
References
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NICE, “Gastro-oesophageal reflux disease and dyspepsia in adults: investigation and management”
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NHS, “Gastro-oesophageal reflux disease (GORD)”
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British National Formulary, “Dyspepsia and gastro-oesophageal reflux disease”
