Omeprazole: Clinical Evidence & Trials
Omeprazole is a proton pump inhibitor (PPI) that reduces gastric acid production and is used to treat acid reflux, GERD, and peptic ulcers.
PPIs are the most effective acid-suppressing agents available, with robust evidence for GERD, peptic ulcer disease, and H. pylori eradication.
Evidence Strength
Level A (Strong) for GERD, peptic ulcer disease, H. pylori eradication, NSAID-induced gastropathy prevention, and Zollinger-Ellison syndrome.
Key Clinical Trial Findings
- •Cochrane review (2011) — PPIs superior to H2-blockers for erosive GERD healing at 8 weeks; NNT ≈ 3 vs H2RAs
- •H. pylori eradication — standard triple therapy (PPI + clarithromycin + amoxicillin) achieves 70–85% eradication; bismuth quadruple therapy >90%
- •NSAID gastroprotection — PPI co-prescription reduces NSAID-induced ulcer by ~80% (Lancet 2002 systematic review)
- •FAMOUS trial — omeprazole reduced NSAID-related gastrointestinal events vs placebo in arthritis patients
- •Multiple RCTs — PPIs achieve faster ulcer healing than H2RAs (NNT ≈ 3 at 4 weeks for peptic ulcer)
Numbers Needed to Treat (NNT)
GERD healing at 8 weeks: NNT ≈ 3 vs H2-blockers. NSAID ulcer prevention: NNT ≈ 5 over 6 months. H. pylori eradication (combined regimen): NNT ≈ 1.5 vs no eradication for ulcer healing.
Guideline Recommendations
First-line for GERD (NICE, ACG, AGA). Essential in H. pylori eradication regimens (Maastricht V/Florence Consensus 2017). NSAID guidelines recommend PPI for at-risk patients. Long-term use should be reviewed annually for deprescribing.
Conditions Treated with Omeprazole
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