Diltiazem

證據等級: L5

預測適應症: 1 個

Diltiazem: From Hypertension / Angina to Susceptibility to Ischemic Stroke

One-Sentence Summary

Diltiazem is a well-established L-type calcium channel blocker (CCB) classically used for hypertension, angina pectoris, and rate control in atrial fibrillation. The TxGNN model predicts it may confer protection against susceptibility to ischemic stroke, however no supporting clinical trials or published literature were identified for this specific indication pairing — making this a model-only prediction at present.

Quick Overview

Item	Content
Original Indication	Hypertension, angina pectoris, atrial fibrillation (rate control)
Predicted New Indication	Susceptibility to Ischemic Stroke
TxGNN Prediction Score	99.08%
Evidence Level	L5 — Model prediction only, no supporting studies identified
India Market Status	Not Marketed
Number of Registrations	0
Recommended Decision	Hold

Why is This Prediction Reasonable?

Currently, detailed mechanism of action data is not available in this evidence pack. Based on well-established pharmacological knowledge, Diltiazem is a non-dihydropyridine L-type calcium channel blocker (benzothiazepine class). It reduces intracellular calcium influx in vascular smooth muscle and cardiac conduction tissue, thereby producing vasodilation, blood pressure reduction, and heart rate slowing.

Three mechanistic pathways plausibly link Diltiazem to reduced ischemic stroke susceptibility: ① Sustained blood pressure reduction — hypertension is the single most important modifiable risk factor for ischemic stroke; ② Heart rate and rhythm control in atrial fibrillation — AF is a major source of cardioembolic stroke, and rate control with Diltiazem may indirectly reduce thromboembolic events; ③ Preclinical data suggest CCBs may attenuate neuronal calcium overload during ischemia, offering a degree of neuroprotective effect.

However, the predicted indication is framed as “susceptibility” — a preventive rather than acute-treatment context. The existing evidence base for Diltiazem as a primary stroke-prevention agent is limited compared to other antihypertensives (e.g., ACE inhibitors, ARBs) that have stronger stroke outcome data. The ontology label also carries the prefix “obsolete,” suggesting this disease term may be deprecated or underspecified in the knowledge graph, which adds further uncertainty to the prediction target.

Clinical Trial Evidence

Currently no related clinical trials registered for Diltiazem in ischemic stroke susceptibility.

Literature Evidence

Currently no related literature available for this specific drug–indication pair.

India Market Information

No marketing authorizations for Diltiazem are currently registered in India according to this evidence pack.

Safety Considerations

Drug Interactions: Diltiazem has a notably broad interaction profile — 369 interactions have been identified (source: DDInter). Key interactions include:

Interacting Drug	Severity	Clinical Note
Loperamide	Major	Risk of serious cardiac arrhythmia; concurrent use requires close monitoring or avoidance
Hydrocortisone	Moderate	Corticosteroids may attenuate antihypertensive effect
Dexamethasone	Moderate	As above; CYP3A4 interaction may alter Diltiazem plasma levels
Budesonide	Moderate	CYP3A4-mediated increase in budesonide exposure
Pioglitazone	Moderate	Diltiazem may increase pioglitazone levels via CYP2C8 inhibition
Canagliflozin	Moderate	Pharmacodynamic interaction; monitor blood pressure and renal function
Morphine	Moderate	Additive hypotension and CNS depression risk
Acetylsalicylic acid	Moderate	Potential pharmacodynamic interaction; monitor bleeding and cardiac effects
Aprepitant	Moderate	CYP3A4 substrate interaction; monitor for increased Diltiazem effect
Calcium salts (multiple)	Moderate	Calcium supplementation may antagonise CCB effect

Note: Detailed prescriber warnings and contraindications were not available in this evidence pack. Please refer to the approved package insert for complete safety information.

Conclusion and Next Steps

Decision: Hold

Rationale: The TxGNN model assigns a high confidence score (99.08%), and the mechanistic hypothesis linking Diltiazem’s antihypertensive and rate-control properties to reduced ischemic stroke susceptibility is biologically plausible. However, zero clinical trials and zero publications were found to support this specific repurposing direction; the disease term itself is flagged as “obsolete” in the ontology, introducing ambiguity about the precise clinical target. A Hold decision is appropriate until the evidence base and indication definition are clarified.

To proceed, the following is needed:

Clarify the indication target: The ontology term “obsolete susceptibility to ischemic stroke” should be mapped to a current, active disease ontology term (e.g., MONDO or ICD-10) to ensure the prediction target is clinically actionable
Mechanism of action (MOA) data: Retrieve full DrugBank MOA record for Diltiazem to support a formal mechanistic rationale document
Regulatory safety data: Download and parse the approved prescribing information (package insert) to obtain complete warnings, contraindications, and special population guidance before any clinical evaluation is initiated
Targeted literature review: Conduct a broader PubMed search using related terms (e.g., “calcium channel blocker stroke prevention,” “Diltiazem cerebrovascular”) to determine if evidence exists under adjacent search terms not captured by the current query
Comparative positioning: Evaluate how Diltiazem compares to other antihypertensives (amlodipine, lisinopril, losartan) that have established stroke-reduction outcome data, to assess whether a repurposing claim adds clinical value
India regulatory pathway assessment: Confirm whether Diltiazem can be licensed or imported for investigational use under CDSCO regulations before planning any prospective study
Disclaimer

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