Dextromethorphan Hydrobromide

證據等級: L5

預測適應症: 0 個

Dextromethorphan Hydrobromide: Drug Repurposing Evaluation Report

One-Sentence Summary

Dextromethorphan hydrobromide is a widely used antitussive (cough suppressant) with 35 registrations in Malaysia. However, the TxGNN model did not generate any predicted new indications for this drug in the current analysis cycle, and critical data gaps (MOA, safety labelling, DrugBank mapping) remain unresolved.

Quick Overview

Item	Content
Original Indication	Antitussive (cough suppressant) — licence-level indication text not yet captured
Predicted New Indication	None (no TxGNN prediction available)
TxGNN Prediction Score	N/A
Evidence Level	N/A
Malaysia Market Status	✓ Marketed
Number of Registrations	35
Recommended Decision	Hold

Why is This Prediction Reasonable?

No Prediction Was Generated

The TxGNN model did not return any repurposing candidates for dextromethorphan hydrobromide. This may be due to one or more of the following reasons:

Missing DrugBank ID mapping — The evidence pack shows drugbank_id: null. Without a valid DrugBank identifier (the expected ID is DB00514), the drug cannot be located in the TxGNN knowledge graph, and therefore no drug–disease edge predictions can be computed.
Incomplete upstream data — The original indications array is empty and the mechanism of action is listed as a data gap. These missing inputs may have prevented the prediction pipeline from executing for this compound.

Known Pharmacology (General Knowledge)

Dextromethorphan is a synthetic morphinan derivative that acts primarily as an NMDA receptor antagonist and sigma-1 receptor agonist. It is the d-isomer of levorphanol’s methyl ether and, unlike its l-isomer, has no opioid analgesic activity at therapeutic doses. Its primary approved use worldwide is as a non-narcotic antitussive for the temporary relief of cough. More recently, dextromethorphan (in combination with quinidine as Nuedexta®) has been approved for pseudobulbar affect (PBA), demonstrating that this molecule does have proven CNS activity beyond cough suppression — a fact that could, in principle, support future repurposing hypotheses in neurological or psychiatric indications.

Clinical Trial Evidence

No predicted indication was generated; therefore, no targeted clinical trial search was performed.

Currently no related clinical trials to display.

Literature Evidence

No predicted indication was generated; therefore, no targeted literature search was performed.

Currently no related literature available.

Malaysia Market Information

Authorization Number	Product Name	Dosage Form	Approved Indication
(not captured)	(not captured)	(not captured)	(not captured)

Note: 35 product registrations were identified in the NPRA database, but the detailed licence-level data (authorization numbers, product names, dosage forms, and approved indication text) has not yet been captured into the evidence pack. All five licence slots are currently empty.

Safety Considerations

Please refer to the package insert for safety information.

Key safety data (warnings, contraindications, and drug interactions) could not be retrieved in this evidence collection cycle. This is classified as a Blocking data gap (DG001) that must be resolved before proceeding to Stage 1 safety evaluation.

Data Gaps Summary

The following unresolved data gaps were identified and must be addressed before this candidate can be re-evaluated:

Gap ID	Category	Item	Severity	Remediation
DG001	Drug Level	Package insert warnings & contraindications	Blocking	Download and parse package insert PDF from TFDA website
DG002	Drug Level	Mechanism of action (MOA)	High	Query DrugBank API (expected ID: DB00514)
—	Drug Level	DrugBank ID mapping	High	Confirm mapping to DB00514 and re-run prediction pipeline
—	Drug Level	Original indication text	Medium	Extract from licence records
—	Regulatory	Licence details (all 35 records)	Medium	Re-query NPRA database with full field extraction

Conclusion and Next Steps

Decision: Hold

Rationale: No repurposing prediction was generated by TxGNN, most likely because the DrugBank ID mapping is missing (null), which prevents the drug from being located in the knowledge graph. Additionally, blocking data gaps in safety labelling make it impossible to proceed to safety evaluation. This candidate cannot be evaluated until upstream data issues are resolved.

To proceed, the following is needed:

Resolve DrugBank ID mapping — Confirm that dextromethorphan hydrobromide maps to DrugBank ID DB00514 and re-inject into the prediction pipeline
Re-run TxGNN prediction — Once the DrugBank ID is mapped, re-execute both KG and DL prediction methods
Retrieve package insert safety data (DG001) — Download the Malaysian/Taiwan package insert PDF and extract warnings, contraindications, and interaction data
Query DrugBank API for MOA (DG002) — Populate the mechanism of action field to enable mechanistic plausibility analysis
Complete licence-level data extraction — Capture authorization numbers, product names, dosage forms, and approved indications for the 35 registered products
Disclaimer

This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.