Omeprazole vs Famotidine: side-by-side comparison
Omeprazole (Proton pump inhibitor) and Famotidine (H2-receptor antagonist) belong to different therapeutic classes and are rarely substitutes for each other. The comparison is useful when a single patient is weighing both options for adjacent or overlapping needs.
| Property | Omeprazole | Famotidine |
|---|---|---|
| Therapeutic class | Proton pump inhibitor | H2-receptor antagonist |
| CAS | 73590-58-6 | 76824-35-6 |
| ATC | A02BC01 | A02BA03 |
| Molecular weight | 345.42 g/mol | 337.45 g/mol |
| Brands with this active ingredient | 1 | 1 |
What they share
Omeprazole and Famotidine share the common regulatory framework for prescription active ingredients, bioequivalence standards for generics, and pharmacist oversight. Beyond that, points in common are limited.
Key differences
Omeprazole acts by a different mechanism than Famotidine, with indications that barely overlap. Comparing the two is useful when a clinician has mentioned both in the same context or the patient wants to understand why one was prescribed instead of the other.
Mechanisms compared
Omeprazole: Omeprazole is a substituted benzimidazole prodrug activated in the acidic environment of the gastric parietal cell, where it irreversibly inhibits the H+/K+-ATPase enzyme — the proton pump responsible for the final step… Famotidine: Famotidine reversibly and competitively blocks histamine H2 receptors on gastric parietal cells, reducing both basal and stimulated gastric acid secretion.
Indications compared
Omeprazole: Omeprazole is approved in adults and children for the treatment of gastro-oesophageal reflux disease, including erosive oesophagitis healing, peptic ulcer disease, prevention of NSAID-induced ulcers, Zollinger-Ellison sy… Famotidine: Famotidine is approved in adults and children for short-term treatment of active duodenal and gastric ulcer, maintenance therapy of duodenal ulcer, gastro-oesophageal reflux disease, Zollinger-Ellison syndrome and other…
Safety profile
Omeprazole: Common adverse effects include headache, gastrointestinal symptoms and dizziness. Famotidine: Famotidine is generally well tolerated.
Frequently asked questions
Is Omeprazole better than Famotidine? ▾
Omeprazole and Famotidine are not "better or worse" — they treat different things. The sensible question is which fits your specific need.
Can Omeprazole and Famotidine be combined? ▾
Whether they can be combined depends on the indications and the interaction profile of each. If both are in a single prescription, the prescriber has weighed it; in self-medication they should never be combined.
Do they have the same side-effect profile? ▾
No — they belong to different classes and have distinct side-effect profiles. Each has its own prescribing information.
Products with Omeprazole
Products with Famotidine
The information on this website is provided for reference and educational purposes only. It does not replace consultation with a qualified healthcare professional.