Famotidine
| Evidence Level: L4 | Predicted Indications: 10 |
Table of Contents
Famotidine: From Gastric Ulcer and Reflux Disease to Duodenogastric Reflux
One-Sentence Summary
Famotidine is an H2-receptor blocker, originally used to reduce stomach acid in gastric and duodenal ulcers, gastroesophageal reflux disease and Zollinger-Ellison syndrome. The TxGNN model predicts it may be effective for duodenogastric reflux (reflux of duodenal contents back into the stomach). Support is thin: 0 registered clinical trials and 2 publications, both indirect.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Gastric ulcer, gastroesophageal reflux disease, duodenal ulcer, Zollinger-Ellison syndrome (the Singapore licences in the data compiled for this report carry no indication text, so this list comes from the knowledge-graph indication records) |
| Predicted New Indication | Duodenogastric reflux |
| TxGNN Prediction Score | 99.99% |
| Evidence Level | L4 |
| Singapore Market Status | ✓ Marketed |
| Number of Registrations | 11 |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Detailed mechanism-of-action data are not available in the compiled data. Famotidine belongs to the H2-receptor antagonist class. It reduces gastric acid secretion, and its efficacy in acid-related upper gastrointestinal disease is established.
Reducing acid load may ease symptoms and mucosal injury in mixed gastroduodenal reflux. This is the main reason the prediction is plausible, and it is only a partial fit. Famotidine does not address bile reflux directly, which is a central feature of duodenogastric reflux. It would act on the acid component only.
The high TxGNN score (rank 448 among predictions for this drug) likely reflects closeness to the approved acid-related indications in the knowledge graph, not independent proof of benefit.
Clinical Trial Evidence
Currently no related clinical trials registered.
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 12532466 | 2003 | Clinical study (critically ill patients) | World J Gastroenterol | Investigated the effect of famotidine on gastroesophageal and duodeno-gastro-esophageal reflux in critically ill patients, and explored possible mechanisms and related factors. The abstract gives no results. |
| 16259441 | 2004 | Review / clinical report | Eksp Klin Gastroenterol | Evaluated famotidine 20 mg twice daily in early-stage gastroduodenal reflux disease (Savary-Miller grades 0–1), using clinical and endoscopic assessment. |
Both publications are small and indirect, and neither is a randomised controlled trial.
Singapore Market Information
Famotidine has 11 valid single-ingredient registrations in Singapore, all oral tablets (film-coated or plain), in 20 mg and 40 mg strengths. Approved indication text is not listed for these licences. Five main authorisations:
| Authorization Number | Product Name | Dosage Form |
|---|---|---|
| SIN10595P | SUNPEPCIN 20 TABLET 20 mg | Tablet, film coated |
| SIN05641P | FAMOPSIN 20 TABLET 20 mg | Tablet, film coated |
| SIN10470P | PHARMA FAMOTIDINE TABLET 20 mg | Tablet, film coated |
| SIN05640P | FAMOPSIN 40 TABLET 40 mg | Tablet, film coated |
| SIN07569P | FAMOTIN TABLET 20 mg | Tablet |
Safety Considerations
- Drug Interactions: 100 interactions are recorded, mostly Moderate severity. Examples:
- Moderate: abiraterone, acalabrutinib, tramadol, amiodarone, amitriptyline, aripiprazole, aminophylline, salbutamol.
- Minor: alendronic acid, aluminium hydroxide.
- Disease-related cautions (knowledge-graph records, not label text): Contraindication links include kidney disease or impaired renal function, liver disease, gallbladder disease, nephrolithiasis, hypercalcaemia and related calcium or phosphorus disorders, diarrhoeal disease, constipation, and gastric cancer or gastric neoplasm. These need verification against the approved package insert.
Please refer to the package insert for full warnings and contraindications.
Conclusion and Next Steps
Decision: Hold
Rationale: The prediction is mechanistically plausible only for the acid component of duodenogastric reflux. Evidence is limited to two indirect publications and no registered trials. Famotidine has no clear effect on bile reflux, which is central to this condition.
To proceed, the following is needed:
- A controlled clinical study of famotidine in duodenogastric reflux, with endoscopic or symptom endpoints and a comparison against a proton pump inhibitor.
- Evidence on whether acid suppression alone is clinically meaningful when bile reflux is the main driver.
- Singapore package insert warnings, contraindications and approved indication text.
- Detailed mechanism-of-action data.
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.