Skip to main content

What the FDA labels say about taking them together

Carbamazepine and clonazepam

Carbamazepine's FDA label of August 20, 2026 names clonazepam in its drug interactions section, and clonazepam's label names carbamazepine too. The clonazepam label: “Cytochrome P-450 inducers, such as phenytoin, carbamazepine, lamotrigine, and phenobarbital induce clonazepam metabolism, causing an approximately 38% decrease in plasma clonazepam levels.”

Check it at the source: the carbamazepine FDA label on DailyMed (effective August 20, 2026, Novartis Pharmaceuticals Corporation); the clonazepam FDA label on DailyMed (effective December 1, 2025, H2-Pharma, LLC).

What does the carbamazepine label say about clonazepam?

Carbamazepine label, drug interactions

In addition, Tegretol causes, or would be expected to cause, decreased levels of the following drugs, for which monitoring of concentrations or dosage adjustment may be necessary: acetaminophen, albendazole, alprazolam, aprepitant, buprenorphone, bupropion, citalopram, clonazepam, clozapine, corticosteroids (e.g., prednisolone, dexamethasone), cyclosporine, dicumarol, dihydropyridine calcium channel blockers (e.g., felodipine), doxycycline, eslicarbazepine, ethosuximide, everolimus, haloperidol, imatinib, itraconazole, lamotrigine, levothyroxine, methadone, methsuximide, mianserin, midazolam, olanzapine, oral and other hormonal contraceptives, oxcarbazepine, paliperidone, phensuximide …

Carbatrol label (Takeda Pharmaceuticals America, Inc., August 17, 2026), drug interactions

Acetaminophen, albendazole, alprazolam, aprepitant, buprenorphine, apixaban (6), bupropion, buspirone, citalopram, clobazam, clonazepam, clozapine, corticosteroids (e.g. prednisolone, dexamethasone), cyclosporin, dabigatran (6), delavirdine, desipramine, diazepam, dicumarol, dihydropyridine calcium channel blockers (e.g., felodipine), doxycycline, edoxaban (6), eslicarbazepine, ethosuximide, everolimus, felbamate, haloperidol, imatinib, itraconazole, lamotrigine, levothyroxine, lorazepam, methadone, methsuximide, midazolam, mirtazapine, nefazodone, nortriptyline, olanzapine, oral and other hormonal contraceptives (2), oxcarbazepine, paliperidone, phenytoin (3), praziquantel, protease …

Equetro label (Validus Pharmaceuticals LLC, August 19, 2025), drug interactions

Drugs metabolized by CYP3A4 or CYP1A2 include the following: Acetaminophen, albendazole, alprazolam, aprepitant, buprenorphone, bupropion, buspirone, citalopram, clobazam, clonazepam, clozapine, cyclosporin, delavirdine, desipramine, diazepam, dicumarol, dihydropyridine calcium channel blockers (e.g., felodipine), doxycycline, ethosuximide, everolimus, felbamate, glucocorticoids, haloperidol, imatinib, itraconazole, lamotrigine, levothyroxine, lorazepam, methadone, methsuxamide, mianserin, midazolam, mirtazapine, nefazodone, olanzapine, oral and other hormonal contraceptives, oxcarbazepine, paliperidone, phenytoin, praziquantel, quetiapine, risperidone, sertraline, sirolimus, tadalafil …

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 clonazepam label say about carbamazepine?

Clonazepam label, drug interactions

Cytochrome P-450 inducers, such as phenytoin, carbamazepine, lamotrigine, and phenobarbital induce clonazepam metabolism, causing an approximately 38% decrease in plasma clonazepam levels.

Source: FDA drug label (Klonopin), NDA017533 (Cheplapharm), as published by H2-Pharma, LLC, effective December 1, 2025 (SPL set cfa0d79a-843c-4b88-95a1-e9511d649ca1), 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

42Carbamazepine generic labelers
31Clonazepam generic labelers
CarbamazepineClonazepam
Labeled forBipolar disorder, Seizures and epilepsySeizures and epilepsy, Anxiety
Boxed warningYesYes
Pharmacy cost (NADAC)$0.119 per tablet 200 mg tablet$0.0244 per tablet 1 mg tablet
Shortage nowA presentation being discontinuedIn shortage

Source: FDA NDC Directory, CMS NADAC of October 7, 2026 and the FDA Drug Shortage Database (FDA files October 8, 2026)

What next?