What the FDA labels say about taking them together
Carbamazepine and loxapine
Carbamazepine's FDA label of August 20, 2026 names loxapine in its drug interactions section; the loxapine labels PlainMeds reads (2) do not name carbamazepine. The carbamazepine label: “Accordingly, the dosage of Carbatrol should be adjusted and/or the plasma levels monitored when used concomitantly with loxapine, quetiapine, or valproic acid.”
Check it at the source: the carbamazepine FDA label on DailyMed (effective August 20, 2026, Novartis Pharmaceuticals Corporation); the loxapine FDA label on DailyMed (effective February 26, 2025, Elite Laboratories, Inc.).
What does the carbamazepine label say about loxapine?
Carbamazepine label, drug interactionsAccordingly, the dosage of Tegretol should be adjusted and/or the plasma levels monitored when used concomitantly with loxapine, quetiapine, valproic acid, or brivaracetam.
Equetro label (Validus Pharmaceuticals LLC, August 19, 2025), drug interactionsDrugs that Inhibit Epoxide H ydrolase and CYP3A4 Clarithromycin, erythromycin, loxapine, quetiapine, and valproate also inhibit epoxide hydrolase, resulting in increased levels of the active metabolite carbamazepine-10,11-epoxide [see Clinical Pharmacology ( 12.3 )].
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 loxapine label say about carbamazepine?
Loxapine's label (effective February 26, 2025) and its 1 other brand-application label do not name carbamazepine in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Loxapine), Elite Laboratories, Inc., effective February 26, 2025 (SPL set a0cc7bb6-075f-47d1-8935-eb77a29d8c45), 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 | Loxapine | |
|---|---|---|
| Labeled for | Bipolar disorder, Seizures and epilepsy | Schizophrenia |
| Boxed warning | Yes | Yes |
| Pharmacy cost (NADAC) | $0.119 per tablet 200 mg tablet | $0.468 per capsule 10 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