Carbamazepine
| Evidence Level: L5 | Predicted Indications: 3 |
Table of Contents
- Carbamazepine
- Pharmacist Assessment Report
- Carbamazepine: Voltage-gated sodium channel blocker → trigeminal nerve neoplasm
- One-Sentence Summary
- Quick Overview
- Why is This Prediction Reasonable?
- Clinical Trial Evidence
- Literature Evidence
- Australia Market Information
- Safety Considerations
- Conclusion and Next Steps
- Disclaimer
Carbamazepine: Voltage-gated sodium channel blocker → trigeminal nerve neoplasm
One-Sentence Summary
Carbamazepine is a long-established anticonvulsant that is thought to act by blocking voltage-gated sodium channels. The TxGNN model predicts it may be relevant to trigeminal nerve neoplasm, but the data compiled for this report contain no clinical trials and no publication that studies carbamazepine as a treatment for this tumour. Any benefit would most likely be symptomatic relief of tumour-related facial nerve pain, not an effect on the tumour itself.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Not recorded in the local data |
| Predicted New Indication | trigeminal nerve neoplasm |
| TxGNN Prediction Score | 1.0000 |
| Evidence Level | L5 |
| Australia Market Status | Listed on the PBS Schedule (1 of 1 items) – TGA (ARTG) registration status is not included in this data |
| Number of PBS Items | 1 (valid: 1) |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Detailed mechanism of action data are not available in the data compiled for this report. Carbamazepine is generally understood to block voltage-gated sodium channels, which reduces abnormal, repetitive firing in nerve cells. This is the basis for its use in nerve pain conditions such as trigeminal neuralgia.
Tumours of the trigeminal nerve or nearby structures (for example schwannoma, meningioma, lymphoma or dermoid cyst) often present with trigeminal neuralgia-type facial pain. In several of the case reports retrieved, patients were first given carbamazepine for that pain, with variable results, and the tumour was found later.
There is no evidence that carbamazepine has an antitumour effect. The high score most likely reflects how closely related trigeminal neuralgia and trigeminal nerve disease are in the model’s network, not a disease-modifying action. Any potential benefit would be limited to symptom control, so this is not true repurposing for the neoplasm.
Clinical Trial Evidence
Currently no related clinical trials registered.
Literature Evidence
The retrieved publications are mostly reviews of trigeminal neuralgia and case reports of tumours or lesions that caused it. None tests carbamazepine as a treatment for trigeminal nerve neoplasm.
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 36824641 | 2022 | Review | Acta Clin Croat | Treatment options for trigeminal neuralgia, which can be caused by vascular compression or a tumour |
| 17997704 | 2007 | Review | Expert Rev Neurother | Overview of medical and surgical treatments for trigeminal neuralgia |
| 30741017 | 2023 | Case report | Br J Neurosurg | Primary lymphoma of the trigeminal nerve; carbamazepine did not improve facial pain |
| 25433061 | 2014 | Case report | No Shinkei Geka | Cerebellopontine angle lipoma with trigeminal neuralgia; pain not adequately controlled by carbamazepine because of side effects |
| 12590697 | 2003 | Case report | Neurosurgery | Trigeminal nerve sarcoid granuloma mimicking schwannoma |
| 33989821 | 2021 | Case report | World Neurosurg | Petroclival meningioma causing trigeminal neuralgia, treated surgically |
| 32454201 | 2020 | Case report | World Neurosurg | Endoscopic resection of a pterygopalatine fossa schwannoma |
| 22647513 | 2012 | Case report | No Shinkei Geka | Combined glossopharyngeal and trigeminal neuralgia; carbamazepine first-line, surgery if it fails |
| 3181365 | 1988 | Preclinical (rat) | Exp Neurol | Intravenous carbamazepine inhibited spontaneous activity in experimental nerve neuromas |
| 15235745 | 2004 | Case report | Arq Neuropsiquiatr | Primary melanoma of Meckel’s cave; pain not relieved by carbamazepine |
Australia Market Information
| ARTG Number | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| 14051M | Tegretol Liquid | Oral suspension 100 mg per 5 mL, 300 mL | Not recorded in the local data |
Safety Considerations
Safety information from the product label was not available in the data compiled for this report. Please refer to the TGA-approved Product Information (PI) for warnings and contraindications.
Drug Interactions (100 interactions were identified; examples of the major ones are listed):
- Major: clarithromycin, eliglustat
- Moderate (examples): doxycycline, hydrocortisone, dexamethasone, bupropion, morphine, metronidazole, cimetidine, pioglitazone, aprepitant, canagliflozin
Carbamazepine is a strong enzyme inducer, so a full interaction review is needed before any use alongside other medicines.
Conclusion and Next Steps
Decision: Hold
Rationale: No clinical trial or publication tests carbamazepine as a treatment for trigeminal nerve neoplasm, so the evidence level is L5. The plausible benefit is symptomatic relief of tumour-related nerve pain, which is not a disease-modifying effect, and the case reports show carbamazepine often failed to control pain in these patients.
To proceed, the following is needed:
- Product Information warnings and contraindications from the TGA-approved PI
- Mechanism of action data
- Controlled or cohort data on carbamazepine for pain caused by trigeminal nerve tumours
- A drug-interaction review for the patient population concerned
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.