What the FDA labels say about taking them together
Carbamazepine and ensitrelvir
Ensitrelvir's FDA label of June 3, 2026 names carbamazepine in its drug interactions section; the carbamazepine labels PlainMeds reads (3) do not name ensitrelvir. The ensitrelvir label: “Co-administration is contraindicated due to potential loss of virologic response.”
Check it at the source: the carbamazepine FDA label on DailyMed (effective August 20, 2026, Novartis Pharmaceuticals Corporation); the ensitrelvir FDA label on DailyMed (effective June 3, 2026, Shionogi Inc.).
What does the carbamazepine label say about ensitrelvir?
Carbamazepine's label (effective August 20, 2026) and its 2 other brand-application labels do not name ensitrelvir in these sections. A label lists what its studies and reports found; it is not a complete list.
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 ensitrelvir label say about carbamazepine?
Ensitrelvir label, drug interactionsDrug Class: Anticonvulsants; Drug (s) within Class: carbamazepine See, phenytoin; Effect on Drug Concentration: ↓ ensitrelvir; Clinical Comment: Co-administration is contraindicated due to potential loss of virologic response.
Source: FDA drug label (XOCOVA), Shionogi Inc., effective June 3, 2026 (SPL set 526acf60-abc3-2cc2-e063-6294a90affa6), 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 | Ensitrelvir | |
|---|---|---|
| Labeled for | Bipolar disorder, Seizures and epilepsy | COVID-19 |
| Boxed warning | Yes | No |
| Pharmacy cost (NADAC) | $0.119 per tablet 200 mg tablet | n/a |
| 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