SHEET /vs/famotidine-vs-omeprazole · COMPARISON
Famotidine vs Omeprazole: what is the difference?
How they differ
Both reduce stomach acid and they act at different points in the same machinery. Famotidine is an H2 blocker: it blocks the histamine receptor on the acid-producing cell, which turns the signal down and works within an hour. Omeprazole is a proton pump inhibitor: it permanently disables the pump that actually moves acid into the stomach, so it takes days of repeated use to reach full effect but reduces acid far more completely. That is why one is useful for occasional heartburn and the other for sustained reduction. Omeprazole needs an acidic environment to activate, which is why its capsules are coated to survive until they are absorbed. Famotidine is the smaller molecule at 337.5 against 345.4 and contains sulfur in two places.
Side by side
| Famotidine | Omeprazole | |
|---|---|---|
| Formula | C8H15N7O2S3 | C17H19N3O3S |
| Molecular weight | 337.5 g/mol | 345.4 g/mol |
| Family | Over-the-counter medicines | Over-the-counter medicines |
| Everyday group | OTC medicine | OTC medicine |
| Functional groups | Amines | Aromatics, Ethers |
| GHS signal wordThe supplier-filed hazard label, not a statement about ordinary use. | not recorded | Warning |
| Oral LD50A single acute animal measure. It ranks nothing about human safety. | not recorded | 4,000 mg/kg (oral, rat) |
| Also sold as | Pepcid | Prilosec, Zegerid |
| CAS number | not recorded | 73590-58-6 |
| PubChem CID | 3325 | 4594 |
Common questions
- What is the difference between Famotidine and Omeprazole?
- Both reduce stomach acid and they act at different points in the same machinery. Famotidine is an H2 blocker: it blocks the histamine receptor on the acid-producing cell, which turns the signal down and works within an hour. Omeprazole is a proton pump inhibitor: it permanently disables the pump that actually moves acid into the stomach, so it takes days of repeated use to reach full effect but reduces acid far more completely.
- Is Famotidine bigger than Omeprazole?
- Omeprazole is the heavier molecule, 345.4 g/mol against 337.5 g/mol for Famotidine. Famotidine is C8H15N7O2S3 and Omeprazole is C17H19N3O3S.
Read the full records: Famotidine and Omeprazole.