What the FDA labels say about taking them together
Atazanavir/cobicistat and naloxone
Atazanavir/cobicistat's FDA label of May 12, 2025 names naloxone in its drug interactions section; the naloxone labels PlainMeds reads (4) do not name atazanavir/cobicistat. The atazanavir/cobicistat label: “Initiation of buprenorphine, buprenorphine/naloxone or methadone in patients taking EVOTAZ: Carefully titrate the dose of buprenorphine, buprenorphine/naloxone or methadone to the desired effect; …”
Check it at the source: the atazanavir/cobicistat FDA label on DailyMed (effective May 12, 2025, E.R. Squibb & Sons, L.L.C.); the naloxone FDA label on DailyMed (effective August 17, 2026, Emergent Devices Inc.).
What does the atazanavir/cobicistat label say about naloxone?
Atazanavir/cobicistat label, drug interactionsConcomitant Drug Class/Specific Drugs: Narcotic analgesics: For treatment of opioid dependence: buprenorphine, naloxone, methadone; Effect b on Concentration: buprenorphine or buprenorphine/naloxone: effects unknown methadone: effects unknown; Clinical Comment: Initiation of buprenorphine, buprenorphine/naloxone or methadone in patients taking EVOTAZ: Carefully titrate the dose of buprenorphine, buprenorphine/naloxone or methadone to the desired effect; use the lowest feasible initial or maintenance dose. Initiation of EVOTAZ in patients taking buprenorphine, buprenorphine/naloxone or methadone: A dose adjustment for buprenorphine, buprenorphine/naloxone or methadone may be needed. …
Source: FDA drug label (EVOTAZ), NDA206353 (Bristol), as published by E.R. Squibb & Sons, L.L.C., effective May 12, 2025 (SPL set 83db29d7-5d85-49d6-8cb6-740473365cf8), via openFDA; the full label on DailyMed
What does the naloxone label say about atazanavir/cobicistat?
Naloxone's label (effective August 17, 2026) and its 3 other brand-application labels do not name atazanavir/cobicistat in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (NARCAN), Emergent Devices Inc., effective August 17, 2026 (SPL set a0ebc83d-2892-40de-bc0a-775ce90b30db), 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/cobicistat | Naloxone | |
|---|---|---|
| Labeled for | HIV | n/a |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | $52.05 per tablet 300 mg-150 mg tablet | $12.74 per mL 2 mg/2 mL syringe |
| 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