Omeprazole and PPIs

PPIs — proton pump inhibitors explained

Proton pump inhibitors (PPIs) are medicines that block acid production in the stomach lining — used for heartburn, GORD (reflux), stomach and duodenal ulcers, and protection when taking NSAIDs (ibuprofen, naproxen) or aspirin long term.

Omeprazole and lansoprazole are the most common in the UK — available on NHS prescription and over the counter for short courses.

How PPIs work

Stomach cells (parietal cells) use a proton pump to secrete hydrochloric acid. PPIs irreversibly block this pump — acid falls significantly for 24 hours per dose.

Unlike antacids (instant neutralisation) or H2 blockers (ranitidine — largely withdrawn), PPIs provide stronger, sustained acid suppression — better for healing erosive oesophagitis and ulcers.

What PPIs treat

• GORD / heartburn — acid reflux into oesophagus
• Peptic ulcers — often with H. pylori eradication antibiotics
• NSAID-associated ulcer prevention
• Zollinger-Ellison syndrome (rare)
• Barrett’s oesophagus — long-term acid suppression reduces progression risk

Common PPIs in the UK

Medicine	Typical dose	Notes
Omeprazole	20 to 40mg daily	OTC 20mg packs — 14 days
Lansoprazole	15 to 30mg daily	Similar to omeprazole
Esomeprazole	20 to 40mg daily	S-isomer of omeprazole
Pantoprazole	20 to 40mg daily	Sometimes if clopidogrel co-prescribed
Rabeprazole	10 to 20mg daily	Less common

How to take

• 30 to 60 minutes before food — usually morning before breakfast
• Swallow whole — do not crush unless dispersible formulation
• Once daily for most — twice daily for severe oesophagitis or Zollinger-Ellison
• OTC courses — max 14 days without GP — if symptoms return, see GP not repeat endlessly

Side effects and long-term considerations

Short term: headache, GI upset — usually mild.

Long term (months to years) — small increased risks:

• Fractures — hip, wrist, spine — especially high doses, elderly, existing osteoporosis
• C. difficile diarrhoea
• Hypomagnesaemia — muscle cramps, arrhythmias (rare)
• Vitamin B12 deficiency — very long term
• Kidney disease association — observational, not proven causal

Benefits usually outweigh risks for genuine indications — but regular review to stop or reduce dose if no longer needed.

Rebound acid hypersecretion

After months of PPI use, stopping abruptly causes temporary surge in acid — worsening heartburn for days to weeks. Not addiction — physiological rebound.

Taper strategy: reduce dose, alternate-day dosing, then stop — use antacids or H2 blocker briefly if needed — GP guides.

Red flags — do not mask

PPIs relieve cancer symptoms temporarily — do not delay diagnosis:

• difficulty swallowing
• unexplained weight loss
• persistent vomiting
• blood in vomit or black stools
• anaemia
• new symptoms over 55

Two-week discontinuation rule: if no improvement after PPI trial, GP referral for gastroscopy.

Interactions

• Clopidogrel — omeprazole/esomeprazole may reduce activation — clinical significance debated — pantoprazole sometimes chosen
• Methotrexate — PPIs may increase levels — monitor
• Drugs needing acid for absorption — ketoconazole, itraconazole, iron — separate timing
• St John’s wort, rifampicin — reduce PPI levels

PPIs vs lifestyle for reflux

First-line for mild GORD:

• weight loss if overweight
• raise head of bed
• avoid late meals, alcohol, trigger foods
• stop smoking

PPI if lifestyle insufficient or erosive disease on endoscopy.

When PPIs are essential long term

• Barrett’s oesophagus
• severe oesophagitis
• ongoing NSAID requirement with ulcer history
• Zollinger-Ellison

In these cases, long-term PPI is standard care — monitor bone health, magnesium, and review dose periodically.

PPIs are effective and widely used — the key is right indication, right duration, and GP review rather than indefinite OTC repetition without investigation.

Common questions

What is the difference between omeprazole and lansoprazole?

Both are PPIs with similar effectiveness. Omeprazole is often once daily; lansoprazole may suit some people who do not respond to omeprazole. Esomeprazole and pantoprazole are alternatives. Choice is often cost and individual response.

Can I take omeprazole long term?

Many people take PPIs for months or years for GORD or Barrett's oesophagus under GP supervision. Long-term use at standard doses has small increased risks — fractures, C. difficile infection, magnesium and B12 deficiency — benefits usually outweigh risks for genuine indications. Regular review to use lowest effective dose.

What are the side effects of omeprazole?

Common — headache, nausea, diarrhoea, constipation, stomach pain — usually mild. Long-term — increased fracture risk (especially high dose long duration), kidney disease association in observational studies, low magnesium. Rare — serious allergic reactions.

Can I stop omeprazole suddenly?

Stopping after long use may cause rebound acid surge — temporary worsening heartburn for days to weeks. Taper — alternate days, then reduce dose — with GP advice if symptoms return severely.

Do PPIs interact with other medicines?

Yes — reduce absorption of some drugs needing acid (ketoconazole, iron). Clopidogrel interaction with omeprazole is debated — pantoprazole sometimes preferred if both needed. Always tell GP and pharmacist all medicines including OTC.

Sources

• NHS — Omeprazole
• NICE — Dyspepsia and GORD