What the FDA labels say about taking them together
Carbamazepine and erlotinib
Erlotinib's FDA label of June 10, 2024 names carbamazepine in its drug interactions section; the carbamazepine labels PlainMeds reads (3) do not name erlotinib. The erlotinib label: “Increase the erlotinib dosage if co-administration with CYP3A4 inducers is unavoidable.”
Check it at the source: the carbamazepine FDA label on DailyMed (effective August 20, 2026, Novartis Pharmaceuticals Corporation); the erlotinib FDA label on DailyMed (effective June 10, 2024, Alembic Pharmaceuticals Limited).
What does the carbamazepine label say about erlotinib?
Carbamazepine's label (effective August 20, 2026) and its 2 other brand-application labels do not name erlotinib in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Tegretol), Novartis Pharmaceuticals Corporation, effective August 20, 2026 (SPL set 8d409411-aa9f-4f3a-a52c-fbcb0c3ec053), via openFDA; the full label on DailyMed
What does the erlotinib label say about carbamazepine?
Erlotinib label, drug interactionsIncrease the erlotinib dosage if co-administration with CYP3A4 inducers (e.g., carbamazepine, phenytoin, rifampin, rifabutin, rifapentine, phenobarbital and St. John's wort) is unavoidable [see Dosage and Administration (2.4)].
Source: FDA drug label (ERLOTINIB HYDROCHLORIDE), Alembic Pharmaceuticals Limited, effective June 10, 2024 (SPL set ab6f3cb3-34a8-4492-a5d7-fb6b055a2d6b), via openFDA; the full label on DailyMed
These are the labels' own sentences. PlainMeds does not grade interactions; a pharmacist or prescriber can say what they mean for one person's medicines.
Both medicines on the record
| Carbamazepine | Erlotinib | |
|---|---|---|
| Labeled for | Bipolar disorder, Seizures and epilepsy | Lung cancer |
| Boxed warning | Yes | No |
| Pharmacy cost (NADAC) | $0.119 per tablet 200 mg tablet | n/a |
| Shortage now | A presentation being discontinued | No current entry |
Source: FDA NDC Directory, CMS NADAC of October 7, 2026 and the FDA Drug Shortage Database (FDA files October 8, 2026)
What next?
- Check more medicines together
- up to five at once