Omeprazole vs Famotidine: side effects in FDA adverse event reports
At a glance
| Omeprazole | Famotidine | |
|---|---|---|
| Drug class | Proton Pump Inhibitor | Histamine-2 Receptor Antagonist |
| Brand names | – | – |
| FAERS reports | 444,238 | 116,682 |
| Serious | 72% | 64% |
| Death outcome | 39,121 | 10,682 |
| Boxed warning | No | No |
Signals both drugs share
| Reaction | Omeprazole | Famotidine | Label screen (A / B) |
|---|---|---|---|
| Acute kidney injury | 23,910 · PRR 8.6 | 4,727 · PRR 5.7 | Not in label — unassessed / Labeled (related wording) |
| Renal failure | 18,173 · PRR 7.3 | 4,119 · PRR 5.7 | Labeled (related wording) / Labeled (related wording) |
| Tubulointerstitial nephritis | 5,325 · PRR 18.4 | 747 · PRR 7.4 | Labeled adverse reaction / Not in label — unassessed |
| Chronic kidney disease | 36,748 · PRR 43.0 | 6,660 · PRR 17.0 | Not in label — unassessed / Not in label — unassessed |
| End stage renal disease | 10,574 · PRR 63.4 | 2,009 · PRR 21.9 | Not in label — unassessed / Not in label — unassessed |
| Gastrooesophageal reflux disease | 9,309 · PRR 6.1 | 2,528 · PRR 5.8 | Not in label — unassessed / Not in label — unassessed |
| Renal injury | 9,730 · PRR 22.3 | 1,498 · PRR 9.4 | Not in label — unassessed / Not in label — unassessed |
| Nephrogenic anaemia | 2,967 · PRR 82.1 | 880 · PRR 41.5 | Not in label — unassessed / Not in label — unassessed |
| Rebound acid hypersecretion | 2,370 · PRR 164.4 | 552 · PRR 39.3 | Likely indication confounding / Likely indication confounding |
| Hyperparathyroidism secondary | 1,340 · PRR 52.7 | 440 · PRR 37.6 | Not in label — unassessed / Not in label — unassessed |
| Nephropathy | 1,411 · PRR 8.2 | 280 · PRR 5.5 | Not in label — unassessed / Not in label — unassessed |
| Chronic kidney disease-mineral and bone disorder | 753 · PRR 111.0 | 241 · PRR 51.7 | Not in label — unassessed / Not in label — unassessed |
| Cholecystitis chronic | 592 · PRR 4.4 | 176 · PRR 4.8 | Not in label — unassessed / Not in label — unassessed |
| Essential hypertension | 371 · PRR 7.7 | 89 · PRR 6.4 | Not in label — unassessed / Not in label — unassessed |
Labeled signals distinctive to Omeprazole
- Pruritus genital — n=428, PRR 10.4 Labeled (related wording)
- Gastric polyps — n=337, PRR 8.1 Labeled (related wording)
- Subacute cutaneous lupus erythematosus — n=315, PRR 10.1 Labeled (related wording)
- Regurgitation — n=314, PRR 4.7 Labeled adverse reaction
Labeled signals distinctive to Famotidine
- Infusion site pain — n=466, PRR 6.8 Labeled (related wording)
- Infusion site pruritus — n=129, PRR 7.7 Labeled (related wording)
Common questions
Which has more reported side effects, Omeprazole or Famotidine?
Omeprazole has 444,238 FAERS reports and Famotidine 116,682. More reports does not mean more dangerous: volume follows how widely and how long a drug has been used, prescription vs over-the-counter status, and publicity. The seriousness share (72% vs 64%) is a better like-for-like signal of the kind of problems reported.
Which side effects do Omeprazole and Famotidine share?
Both drugs carry disproportionality signals for acute kidney injury, renal failure, tubulointerstitial nephritis, chronic kidney disease, end stage renal disease. Shared signals often reflect a shared drug class or the condition both are used for.
Is Omeprazole or Famotidine safer?
FAERS cannot answer that: it has no denominator and no comparator. Use this page to see which risks are already on each label and which signals are unlabeled, then check the prescribing information and your clinician for your situation.
Sources: openFDA FAERS pair statistics (OpenPV build 2026-09-14), FDA labels via openFDA, openFDA count queries for seriousness and deaths. Pair chosen because it is a commonly searched comparison. Generated 2026-10-08.