What the FDA labels say about taking them together
Carbamazepine and verapamil
Carbamazepine's FDA label of August 20, 2026 names verapamil in its drug interactions section, and verapamil's label names carbamazepine too. The verapamil label: “Verapamil therapy may increase carbamazepine concentrations during combined therapy.”
Check it at the source: the carbamazepine FDA label on DailyMed (effective August 20, 2026, Novartis Pharmaceuticals Corporation); the verapamil FDA label on DailyMed (effective April 6, 2026, Zydus Pharmaceuticals (USA) Inc.).
What does the carbamazepine label say about verapamil?
Carbamazepine label, drug interactionsDrugs that have been shown, or would be expected, to increase plasma carbamazepine levels include aprepitant, cimetidine, ciprofloxacin, danazol, diltiazem, macrolides (e.g., erythromycin, clarithromycin), fluoxetine, fluvoxamine, trazodone, omeprazole, oxybutynin, isoniazid, niacinamide (nicotinamide), azoles (e.g., ketaconazole, itraconazole, fluconazole, voriconazole), acetazolamide, verapamil, ticlopidine, grapefruit juice, and protease inhibitors.
Carbatrol label (Takeda Pharmaceuticals America, Inc., August 17, 2026), drug interactionsAcetazolamide, aprepitant, azole antifungals (e.g., ketoconazole, itraconazole, fluconazole, voriconazole), cimetidine, ciprofloxacin, clarithromycin, dalfopristin, danazol, dantrolene, delavirdine, diltiazem, erythromycin, fluoxetine, fluvoxamine, grapefruit juice, ibuprofen, isoniazid, loratadine, macrolides, nefazodone, niacinamide, nicotinamide, olanzapine, omeprazole, oxybutynin, protease inhibitors, propoxyphene, quinine, quinupristin, ticlopidine, troleandomycin, valproate, verapamil, zileuton.
Equetro label (Validus Pharmaceuticals LLC, August 19, 2025), drug interactionsThe following drugs are CYP3A4 inhibitors: Acetazolamide, aprepitant, azole antifungals (e.g., ketoconazole, itraconazole, fluconazole, voriconazole ), cimetidine, ciprofloxacin, clarithromycin, dalfopristin, danazol, dantrolene, delavirdine, diltiazem, erythromycin, fluoxetine, fluvoxamine, grapefruit juice, ibuprofen, isoniazid, loratadine, nefazodone, niacinamide, nicotinamide, olanzapine, omeprazole, oxybutynin, quinine, quinupristin, ticlopidine, troleandomycin, valproate, verapamil, zileuton.
Source: FDA drug label (Carbatrol, NDA020712), Takeda Pharmaceuticals America, Inc., effective August 17, 2026 (SPL set bc03e499-5bac-4293-bff4-6864153a624d), via openFDA
Source: FDA drug label (Equetro, NDA021710), Validus Pharmaceuticals LLC, effective August 19, 2025 (SPL set be478f3c-40f6-47cc-8ab9-f420a9372b1c), via openFDA
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 verapamil label say about carbamazepine?
Verapamil label, drug interactionsCarbamazepine: Verapamil therapy may increase carbamazepine concentrations during combined therapy.
Source: FDA drug label (Verapamil Hydrochloride, NDA020943), Wilshire Pharmaceuticals, Inc., effective November 27, 2024 (SPL set 5f665d08-e1e4-422a-88c2-d8834abf9e1a), via openFDA
Source: FDA drug label (Verapamil hydrochloride), Zydus Pharmaceuticals (USA) Inc., effective April 6, 2026 (SPL set e19ab8d8-dae5-489d-9805-7e7407bea06d), 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 | Verapamil | |
|---|---|---|
| Labeled for | Bipolar disorder, Seizures and epilepsy | High blood pressure, Atrial fibrillation, Angina |
| Boxed warning | Yes | No |
| Pharmacy cost (NADAC) | $0.119 per tablet 200 mg tablet | $0.191 per tablet 180 mg tablet |
| Shortage now | A presentation being discontinued | A presentation being discontinued |
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