What the FDA labels say about taking them together
Carbamazepine and lithium
Carbamazepine's FDA label of August 20, 2026 names lithium in its drug interactions section, and lithium's label names carbamazepine too. The lithium label: “Concomitant use can lower serum lithium concentrations by increasing urinary lithium excretion.”
Check it at the source: the carbamazepine FDA label on DailyMed (effective August 20, 2026, Novartis Pharmaceuticals Corporation); the lithium FDA label on DailyMed (effective December 23, 2025, Glenmark Pharmaceuticals Inc., USA).
What does the carbamazepine label say about lithium?
Carbamazepine label, drug interactionsConcomitant administration of carbamazepine and lithium may increase the risk of neurotoxic side effects.
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 lithium label say about carbamazepine?
Lithium label, drug interactionsClinical Impact: Concomitant use can lower serum lithium concentrations by increasing urinary lithium excretion. Intervention: More frequent serum lithium concentration monitoring. Increase lithium dosage based on serum lithium concentration and clinical response [see Dosage and Administration ( 2.3 )]. Methyldopa, Phenytoin and Carbamazepine
Source: FDA drug label (Lithium Carbonate), Glenmark Pharmaceuticals Inc., USA, effective December 23, 2025 (SPL set 63b3790f-a9b5-47f4-bae1-ddf8b43c13c1), 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 | Lithium | |
|---|---|---|
| Labeled for | Bipolar disorder, Seizures and epilepsy | Bipolar disorder |
| Boxed warning | Yes | Yes |
| Pharmacy cost (NADAC) | $0.119 per tablet 200 mg tablet | $0.104 per capsule 300 mg capsule |
| 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