Lactulose
| 證據等級: L5 | 預測適應症: 10 個 |
目錄
Lactulose: From Established Laxative Use to Obstructive Jaundice
One-Sentence Summary
Lactulose is a synthetic, non-absorbable disaccharide with long-established use as an osmotic laxative and in hepatic encephalopathy. Among five candidate indications generated by the TxGNN model, Obstructive Jaundice is the only one with credible supporting evidence — 1 clinical trial and 20 publications, including one multicentre RCT — while the model’s top-ranked candidates (acute urate nephropathy, nephrolithiasis) were assessed by the underlying evidence pipeline as lacking any plausible mechanistic link and are likely statistical noise.
Note on candidate selection: The evidence pack returned five distinct disease candidates (with duplicate ranks). Two of them — acute urate nephropathy and nephrolithiasis — have zero clinical trials, zero literature, and are explicitly flagged in the source data as having “no identifiable mechanistic link” / “likely prediction noise.” This report therefore focuses on obstructive jaundice, the candidate with the strongest and most interpretable evidence base. Bile duct disease and biliary tract disease are related but weaker, indirect extensions of the same signal and are summarized briefly for context.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Not documented in this evidence pack (no taiwan_regulatory.licenses entries). Lactulose is generically established for chronic constipation and hepatic encephalopathy. |
| Predicted New Indication | Obstructive Jaundice |
| TxGNN Prediction Score | 99.53% |
| Evidence Level | L3 (observational / cohort evidence, incl. one multicentre RCT with mixed replication) |
| Denmark Market Status | Not Marketed |
| Number of Marketing Authorisations | 0 |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Detailed mechanism-of-action data is not available in this evidence pack (original_moa: [Data Gap]). Based on established pharmacological knowledge, lactulose is a non-absorbable disaccharide (osmotic laxative class) that reaches the colon largely intact, where it is fermented by colonic bacteria into short-chain fatty acids. This acidifies the colonic lumen and suppresses urease-producing flora, reducing colonic production and absorption of ammonia and bacterial endotoxin — the same mechanism underlying its established role in hepatic encephalopathy.
In obstructive jaundice, bile salt deficiency in the gut impairs the intestinal mucosal barrier, predisposing patients to bacterial translocation and endotoxaemia. This endotoxin load is implicated in postoperative complications, including renal impairment following biliary surgery. The proposed link — lactulose reducing gut-derived endotoxin absorption to mitigate this cascade — is mechanistically coherent and is not merely a statistical artifact of the embedding space, unlike the acute urate nephropathy and nephrolithiasis candidates, which have no plausible pharmacological connection to lactulose’s laxative/ammonia-lowering action.
However, the strongest available evidence (a 1991 multicentre RCT, see below) tested lactulose as a perioperative renal-protection adjunct in jaundiced surgical patients, not as a treatment for obstructive jaundice itself. A 1997 review (Vogt & Frey) explicitly notes that this reno-protective effect “has not been shown conclusively” in clinical studies, and a 1989 animal study (Shibayama) found lactulose did not prevent bile-duct-ligation-induced hepatic injury. The evidence base is therefore real but mixed, supporting a research hypothesis rather than a confirmed therapeutic effect.
Clinical Trial Evidence
| Trial Number | Phase | Status | Enrollment | Key Findings |
|---|---|---|---|---|
| NCT01090193 | Phase 4 | Completed | 20 | Observational histopathology study of kidney changes in acute obstructive jaundice; does not test lactulose as an intervention — provides disease-mechanism background only. |
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 2032107 | 1991 | RCT (multicentre) | Br J Surg | 102 patients undergoing OJ surgery randomized to lactulose, bile salts, or control to prevent postoperative renal dysfunction. |
| 3768644 | 1986 | Cohort/Experimental | Br J Surg | Oral lactulose reduced peroperative portal and postoperative systemic endotoxaemia in OJ surgical patients (P<0.05). |
| 12957136 | 2003 | Cohort/Review | J Surg Res | Lactulose evaluated in a rabbit bile-duct-ligation model for preventing systemic endotoxaemia after OJ. |
| 15782993 | 2005 | Cohort | Hepatogastroenterology | Argues preoperative hydration plus lactulose is necessary to prevent postoperative renal dysfunction in acute OJ. |
| 9145459 | 1997 | Review | Scand J Gastroenterol Suppl | Notes the hypothesized reno-protective effect of lactulose in OJ “has not been shown conclusively” in clinical studies. |
| 12598962 | 2002 | Animal Study | Pediatr Surg Int | Melatonin + lactulose reduced liver/kidney histopathologic damage in rats with OJ. |
| 2311978 | 1990 | In vitro | Gut | Lactulose inhibited endotoxin-induced TNF production by monocytes, a proposed mechanistic basis for its effect. |
| 2614579 | 1989 | Animal Study | J Pathol | Negative finding: lactulose did not prevent bile infarction or transaminase elevation in bile-duct-ligated rats. |
| 23297639 | 2012 | Cohort | Zh Mikrobiol Epidemiol Immunobiol | Combined biliary decompression + lactulose studied for intestinal microecology in mechanical jaundice. |
| 29428098 | 2018 | Review | HBPD Int | General review of obstructive jaundice pathophysiology and perioperative management (background, not lactulose-specific). |
Denmark Market Information
Lactulose is currently not marketed in Denmark under this evidence pack (market_status: 未上市, 0 marketing authorisations on file). No Laegemiddelstyrelsen or EMA centralised authorisation records were found.
Safety Considerations
No safety data (key warnings, contraindications, or drug interactions) is currently available in this evidence pack — this is flagged as a Blocking data gap (DG001), preventing entry into the initial safety review stage.
Please refer to the approved Summary of Product Characteristics (SmPC) for safety information.
Conclusion and Next Steps
Decision: Hold
Rationale:
- The mechanistic rationale for obstructive jaundice is coherent (endotoxin reduction via gut flora modulation) and supported by one multicentre RCT, but that trial tested a perioperative renal-protection endpoint rather than obstructive jaundice treatment itself, and a subsequent review and an animal study found the effect inconsistent or absent.
- Lactulose has no current marketing authorisation in Denmark, and safety/label data (warnings, contraindications, DDI) is completely unavailable — a blocking gap for any S1 safety assessment.
To proceed, the following is needed:
- TFDA/SmPC-level warnings, contraindications, and drug interaction data (DG001, blocking)
- Confirmed mechanism-of-action documentation (DG002)
- A direct clinical evaluation of lactulose as an obstructive jaundice therapy (not solely as a renal-protection adjunct)
- Assessment of pathway to Danish/EU marketing authorisation, given the drug is currently unregistered in this market
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.