Carbamazepine and Olanzapine interaction
Carbamazepine and Olanzapine: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Carbamazepine (EQUETRO) label · effective 2025-08-19
CNS Depressants The concomitant use of EQUETRO and other CNS depressants can increase the risk of respiratory depression, profound sedation, hypotension, and syncope.
Increased Intraocular Pressure Carbamazepine has mild anticholinergic activity.
Consider reducing the dose of CNS depressants or EQUETRO when using these drugs concomitantly.
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…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, theophylline, topiramate,…
From the Olanzapine (Zyprexa) label · effective 2026-02-11
Carbamazepine: Increased clearance of olanzapine.
Higher daily doses of carbamazepine may cause an even greater increase in olanzapine clearance.
Inducers of CYP1A2 — Carbamazepine therapy (200 mg bid) causes an approximately 50% increase in the clearance of olanzapine.
This increase is likely due to the fact that carbamazepine is a potent inducer of CYP1A2 activity.
Inducers of CYP1A2 or Glucuronyl Transferase — Omeprazole and rifampin may cause an increase in olanzapine clearance.
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.