What the FDA labels say about taking them together
Atazanavir and carbamazepine
Atazanavir's FDA label of August 6, 2025 names carbamazepine in its contraindications section; the carbamazepine labels PlainMeds reads (3) do not name atazanavir. The atazanavir label: “Coadministration of REYATAZ with carbamazepine is contraindicated due to the risk for loss of virologic response and development of resistance.”
Check it at the source: the atazanavir FDA label on DailyMed (effective August 6, 2025, Aurobindo Pharma Limited); the carbamazepine FDA label on DailyMed (effective August 20, 2026, Novartis Pharmaceuticals Corporation).
What does the atazanavir label say about carbamazepine?
Atazanavir label, contraindicationsDrug Class: Anticonvulsants; Drugs within class that are contraindicated with atazanavir capsules: Carbamazepine, phenobarbital, phenytoin
Atazanavir label, drug interactionsConcomitant Drug Class/Specific Drugs: Antiepileptics: carbamazepine; Effect on Concentration of Atazanavir or Concomitant Drug: ↓ atazanavir ↑ carbamazepine; Clinical Comment: Coadministration of atazanavir (with or without ritonavir) with carbamazepine is contraindicated due to the risk for loss of virologic response and development of resistance [see ].
Source: FDA drug label (Reyataz, NDA021567), E.R. Squibb & Sons, L.L.C., effective December 5, 2024 (SPL set 165cff62-b284-4a27-a65d-9ec8a5bfcdd8), via openFDA
Source: FDA drug label (Atazanavir Sulfate), Aurobindo Pharma Limited, effective August 6, 2025 (SPL set 7fbea274-d6b5-4faa-bbf0-05fefab42114), via openFDA; the full label on DailyMed
What does the carbamazepine label say about atazanavir?
Carbamazepine's label (effective August 20, 2026) and its 2 other brand-application labels do not name atazanavir 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
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
| Atazanavir | Carbamazepine | |
|---|---|---|
| Labeled for | HIV | Bipolar disorder, Seizures and epilepsy |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | $2.23 per capsule 300 mg capsule | $0.119 per tablet 200 mg tablet |
| Shortage now | No current entry | A presentation being discontinued |
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