What the FDA labels say about taking them together
Buprenorphine and nelfinavir
Buprenorphine's FDA label of June 5, 2026 names nelfinavir in its drug interactions section; the nelfinavir label PlainMeds reads does not name buprenorphine. The buprenorphine label: “Studies have shown some antiretroviral protease inhibitors (PIs) with CYP3A4 inhibitory activity have little effect on buprenorphine pharmacokinetic and no significant pharmacodynamic effects. …”
Check it at the source: the buprenorphine FDA label on DailyMed (effective June 5, 2026); the nelfinavir FDA label on DailyMed (effective December 11, 2025, AGOURON).
What does the buprenorphine label say about nelfinavir?
Buprenorphine label, drug interactionsAntiretrovirals: Protease inhibitors (PIs) Clinical Impact: Studies have shown some antiretroviral protease inhibitors (PIs) with CYP3A4 inhibitory activity (…) have little effect on buprenorphine pharmacokinetic and no significant pharmacodynamic effects. … Intervention: Monitor patients taking buprenorphine sublingual tablets and atazanavir with and without ritonavir, and reduce dose of buprenorphine sublingual tablets if warranted. Examples: Atazanavir, ritonavir
Brixadi label (Braeburn Inc., December 31, 2025), drug interactionsAntiretrovirals: Protease Inhibitors (PIs) Clinical Impact: Studies have shown some antiretroviral protease inhibitors (PIs) with CYP3A4 inhibitory activity (…) have little effect on buprenorphine pharmacokinetics and no significant pharmacodynamics effects. … Intervention: If treatment with atazanavir with and without ritonavir must be initiated in a patient already treated with BRIXADI, the patient should be monitored for signs and symptoms of over-medication. …
Source: FDA drug label (Brixadi, NDA210136), Braeburn Inc., effective December 31, 2025 (SPL set 5d8a8fd0-8619-422a-a664-d1d2e8970f48), via openFDA
Source: FDA drug label (Sublocade, NDA209819), Indivior Inc., effective July 27, 2026 (SPL set 6189fb21-9432-45f8-8481-0bfaf3ccde95), via openFDA
Source: FDA drug label (Buprenorphine HCl), SpecGx LLC, effective June 5, 2026 (SPL set b60d514d-a88a-4fa2-a5b0-30ac29e04973), via openFDA; the full label on DailyMed
What does the nelfinavir label say about buprenorphine?
Nelfinavir's label (effective December 11, 2025) does not name buprenorphine in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (VIRACEPT), AGOURON, effective December 11, 2025 (SPL set e72c2bc6-9462-4a2e-8e1d-b97592376cbd), 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
| Buprenorphine | Nelfinavir | |
|---|---|---|
| Labeled for | Opioid use disorder, Pain | HIV |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | $0.277 per tablet 2 mg tablet sl | n/a |
| Shortage now | No current entry | 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