Famotidine
| Evidence Level: L5 | Predicted Indications: 4 |
Table of Contents
Famotidine: Duodenal obstruction
One-Sentence Summary
Famotidine is a histamine H2-receptor antagonist originally used for gastric and duodenal ulcers, gastroesophageal reflux disease, and Zollinger-Ellison syndrome.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Not recorded in the local data |
| Predicted New Indication | Duodenal obstruction |
| TxGNN Prediction Score | 0.9999 |
| Evidence Level | L5 (preclinical or mechanism-level support only) |
| Canada Market Status | Marketed (marketed DINs: 18 of 18) |
| Number of DINs | 18 (marketed: 18) |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Detailed mechanism of action data is not available in the data compiled for this report. From general knowledge, famotidine is an H2-receptor antagonist that reduces gastric acid secretion. Its efficacy in gastric and duodenal ulcers is well established.
Several other predictions follow the same pattern. Peptic ulcer disease, gastroduodenitis, and active peptic ulcer disease overlap with existing labelled uses. Duodenal obstruction, peptic ulcer perforation, abnormality of glucagon secretion, and acne have no clear mechanistic link or are mainly surgical or unsupported conditions.
Clinical Trial Evidence
| Trial Number | Phase | Status | Enrollment | Key Findings |
|---|---|---|---|---|
| NCT00843063 | Phase 4 | Completed | 161 | Famotidine vs pantoprazole to prevent recurrent aspirin-induced ulcer; famotidine was inferior (see PMID 19837071) |
| NCT02551744 | NA | Completed | 101 | Pantoprazole vs famotidine for preventing recurrent ulcers in thienopyridine users |
| NCT02418312 | NA | Completed | 228 | H2-receptor antagonist for preventing thienopyridine-related ulcer |
| NCT01180179 | Phase 4 | Completed | 228 | Lansoprazole vs famotidine for preventing recurrent idiopathic ulcer bleeding |
| NCT00229424 | Phase 3 | Completed | 325 | Lafutidine vs famotidine in mild reflux oesophagitis (famotidine is the comparator) |
| NCT00557349 | Phase 4 | Completed | 40 | Zegerid vs famotidine for preventing anastomotic ulcers after gastric bypass |
| NCT03667703 | Phase 4 | Completed | 70 | Stress ulcer prophylaxis vs placebo in infants with congenital heart disease |
| NCT00839488 | Phase 4 | Terminated | 6 | IV pantoprazole vs famotidine for stress ulcer prophylaxis; terminated early, little can be inferred |
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 12532466 | 2003 | Clinical study | World J Gastroenterol | Effect of famotidine on gastroesophageal and duodeno-gastro-esophageal reflux in critically ill patients |
| 16259441 | 2004 | Review/clinical article | Eksp Klin Gastroenterol | Famotidine 20 mg twice daily in early-stage gastroduodenal reflux disease |
Selected publications for the related peptic ulcer prediction:
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 2877912 | 1987 | RCT | Gastroenterology | Placebo-controlled study of famotidine dosing regimens in 384 patients with active duodenal ulcer |
| 19837071 | 2010 | RCT | Gastroenterology | High-dose famotidine was inferior to pantoprazole in preventing recurrent aspirin-related ulcers |
| 2877570 | 1986 | RCT | Am J Med | Famotidine vs ranitidine in 1,031 patients with active duodenal ulcer |
| 2570005 | 1989 | RCT | Digestion | Famotidine vs cimetidine in 119 patients with active duodenal ulcer |
| 2573505 | 1989 | Review | Drugs | Updated review of famotidine pharmacology and use in peptic ulcer disease |
| 2875864 | 1986 | Review | Drugs | Review of famotidine in peptic ulcer disease and Zollinger-Ellison syndrome |
Canada Market Information
| DIN | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| 02022133 | TEVA-FAMOTIDINE | Not available | Not available |
| 02549107 | FAMOTIDINE | Not available | Not available |
| 02509970 | AG-FAMOTIDINE | Not available | Not available |
| 02273357 | MAXIMUM STRENGTH PEPCID AC | Not available | Not available |
| 02243053 | PEPCID COMPLETE | Not available | Not available |
Eighteen licences are valid in total, and none is cancelled. Only the first five are listed here.
Safety Considerations
- Contraindication-related conditions (from the knowledge graph, not label text): kidney disease, impaired renal function, liver disease, gallbladder disease, nephrolithiasis, hypercalcemia, hyperparathyroidism, sarcoidosis, constipation, diarrheal disease, and gastric cancer or neoplasm. These links come from a drug-disease network and should be checked against the official label.
- Drug Interactions: 100 interactions were found. The listed ones are mostly Moderate, for example abiraterone, acalabrutinib, tramadol, amiodarone, amitriptyline, aripiprazole, and salbutamol. Minor interactions include alendronic acid and aluminum hydroxide.
Package insert warnings and contraindications were not available, so please refer to the Health Canada package insert for the full safety information.
Conclusion and Next Steps
Decision: Hold
Rationale:
To proceed, the following is needed:
- Health Canada package insert warnings and contraindications (a blocking gap for safety screening)
- Mechanism of action data from DrugBank
- Prospective controlled trials of famotidine in duodenogastric reflux, with outcomes beyond acid suppression
- Approved indication text, dosage forms, and route information for the Canadian licences
- A review of the knowledge-graph contraindication signals (renal, hepatic, and others) against the label
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.