Pathophysiology: Acid Reflux and Lower Oesophageal Sphincter Dysfunction
Acid reflux (Gastro-oesophageal reflux disease, GORD): Occurs when gastric contents flow back into the oesophagus.
The lower oesophageal sphincter (LES) is a muscular ring at the junction of the oesophagus and stomach. It normally prevents reflux.
Dysfunction: If the LES is weak, relaxes inappropriately, or is disrupted (e.g., by hiatal hernia), stomach acid can enter the oesophagus.
Acid exposure damages the oesophageal lining, causing symptoms and, in severe cases, complications like oesophagitis, strictures, or Barrett’s oesophagus.
Clinical Features
Heartburn: Burning sensation rising from the stomach or lower chest towards the neck.
Regurgitation: Sensation of acid or food coming back into the throat or mouth.
Chest pain: Retrosternal discomfort, may mimic cardiac pain but usually related to meals or lying down.
Other features: sour/bitter taste, bloating, dysphagia (difficulty swallowing), chronic cough, hoarseness.
Diagnosis
pH monitoring: 24-hour oesophageal pH study detects episodes and severity of acid reflux.
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.
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
Weight loss if overweight.
Elevate head of bed and avoid lying down soon after eating.
Reduce meal size and avoid eating late at night.
Avoid triggers: spicy/fatty foods, chocolate, caffeine, alcohol, citrus, peppermint.
Smoking cessation and moderation of alcohol intake.
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
Offer a trial of a PPI for 4–8 weeks for typical symptoms (heartburn, regurgitation).
If symptoms persist, consider double-dose PPI or alternative diagnosis.
Endoscopy if red-flag features (dysphagia, weight loss, anaemia, GI bleeding), persistent symptoms, or for those over 55 with new symptoms.
Advise lifestyle and dietary changes alongside medication.
For maintenance, use the lowest effective PPI dose or on-demand therapy.
Refer for surgical assessment (e.g., fundoplication) if refractory symptoms or complications.
Avoid long-term use of prokinetics and H2 blockers unless PPIs are unsuitable.
References
NICE, “Gastro-oesophageal reflux disease and dyspepsia in adults: investigation and management”
NHS, “Gastro-oesophageal reflux disease (GORD)”
British National Formulary, “Dyspepsia and gastro-oesophageal reflux disease”