What the FDA labels say about taking them together
Carbamazepine and nefazodone
Carbamazepine's FDA label of August 20, 2026 names nefazodone in its contraindications section, and nefazodone's label names carbamazepine too. The carbamazepine label: “This may result in insufficient plasma concentrations of nefazodone and its active metabolite to achieve a therapeutic effect.”
Check it at the source: the carbamazepine FDA label on DailyMed (effective August 20, 2026, Novartis Pharmaceuticals Corporation); the nefazodone FDA label on DailyMed (effective July 31, 2025, Teva Pharmaceuticals USA, Inc.).
What does the carbamazepine label say about nefazodone?
Carbamazepine label, contraindicationsCoadministration of carbamazepine and nefazodone may result in insufficient plasma concentrations of nefazodone and its active metabolite to achieve a therapeutic effect.
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 interactionsDRUG INTERACTIONS Cytochrome (CYP) 3A4 inhibitors, epoxide hydrolase inhibitors, CYP3A4 inducers, drugs metabolized by CYP1A2 or CYP3A4 (oral contraceptives, delavirdine, nefazodone), phenytoin, CNS depressants, lithium, chloroquine, mefloquine ( 7.1 , 7.2 , 7.3 ) Equetro may decrease the effectiveness of hormonal contraceptives.
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 nefazodone label say about carbamazepine?
Nefazodone label, contraindicationsCONTRAINDICATIONS Coadministration of terfenadine, astemizole, cisapride, pimozide, or carbamazepine with nefazodone hydrochloride is contraindicated (see WARNINGS and PRECAUTIONS ).
Nefazodone label, drug interactionsWith coadministration of the two drugs there were significant increases in the steady-state C max and AUC of carbamazepine (23% and 23%, respectively), while the steady-state C max and the AUC of the carbamazepine metabolite, 10,11 epoxycarbamazepine, decreased by 21% and 20%, respectively.
Nefazodone label, warningsInteraction with Carbamazepine The coadministration of carbamazepine 200 mg BID with nefazodone 200 mg BID, at steady state for both drugs, resulted in almost 95% reductions in AUCs for nefazodone and hydroxynefazodone, likely resulting in insufficient plasma nefazodone and hydroxynefazodone concentrations for achieving an antidepressant effect for nefazodone.
Source: FDA drug label (Nefazodone Hydrochloride), Teva Pharmaceuticals USA, Inc., effective July 31, 2025 (SPL set 51ff7db5-aaf9-4c3c-86e6-958ebf16b60f), 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 | Nefazodone | |
|---|---|---|
| Labeled for | Bipolar disorder, Seizures and epilepsy | Depression |
| Boxed warning | Yes | Yes |
| Pharmacy cost (NADAC) | $0.119 per tablet 200 mg tablet | $1.17 per tablet 100 mg tablet |
| 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