What the FDA labels say about taking them together
Nelfinavir and tacrolimus
Nelfinavir's FDA label of December 11, 2025 names tacrolimus in its drug interactions section, and tacrolimus's label names nelfinavir too. The nelfinavir label: “Concentrations of these immunosuppressants and nelfinavir may be increased by coadministration of these agents with nelfinavir.”
Check it at the source: the nelfinavir FDA label on DailyMed (effective December 11, 2025, AGOURON); the tacrolimus FDA label on DailyMed (effective July 17, 2026, Stellon Biotech Inc.).
What does the nelfinavir label say about tacrolimus?
Nelfinavir label, drug interactionsConcomitant Drug Class/Drug Name: Cyclosporine Tacrolimus Sirolimus; Effect on Concentration: ↑ immuno-suppressants ↑ nelfinavir; Clinical Comment: Concentrations of these immunosuppressants and nelfinavir may be increased by coadministration of these agents with nelfinavir.
Source: FDA drug label (VIRACEPT), AGOURON, effective December 11, 2025 (SPL set e72c2bc6-9462-4a2e-8e1d-b97592376cbd), via openFDA; the full label on DailyMed
What does the tacrolimus label say about nelfinavir?
Tacrolimus label, drug interactionsDrug/Substance Class or Name: Strong CYP3A Inhibitors 3: Protease inhibitors (e.g, nelfinavir, telaprevir, boceprevir, ritonavir), azole antifungals (e.g., voriconazole, posaconazole, itraconazole, ketoconazole), antibiotics (e.g., clarithromycin, troleandomycin, chloramphenicol), nefazodone, letermovir, Schisandra sphenanthera extracts; Drug Interaction Effect: May increase tacrolimus whole blood trough concentrations and increase the risk of serious adverse reactions (e.g., neurotoxicity, QT prolongation). A rapid, sharp rise in tacrolimus levels may occur early, despite an immediate reduction of tacrolimus dose [see,,)].; …
Prograf label (Astellas Pharma US, Inc., August 25, 2023), drug interactionsNelfinavir and Grapefruit Juice: Increased tacrolimus concentrations via CYP3A inhibition; avoid concomitant use.
Envarsus Xr label (Veloxis Pharmaceuticals, Inc, February 26, 2025), drug interactionsDrug/Substance Class or Name: Strong CYP3A Inhibitors c,, such as: Protease inhibitors (e.g., nelfinavir, telaprevir, boceprevir, ritonavir or ritonavir containing products), azole antifungals (e.g., voriconazole, posaconazole, itraconazole, ketoconazole), antibiotics (e.g., clarithromycin, troleandomycin, chloramphenicol), nefazodone, Schisandra sphenanthera extracts, cobicistat; Drug Interaction Effect: May increase tacrolimus whole blood trough concentrations and increase the risk of serious adverse reactions (e.g., neurotoxicity, QT prolongation). A rapid, sharp rise in tacrolimus levels may occur early, despite an immediate reduction of tacrolimus dose [see ].; …
Source: FDA drug label (Prograf, NDA050708), Astellas Pharma US, Inc., effective August 25, 2023 (SPL set 7f667de1-9dfa-4bd6-8ba0-15ee2d78873b), via openFDA
Source: FDA drug label (Astagraf Xl, NDA204096), Astellas Pharma US, Inc., effective January 14, 2026 (SPL set 550a5cd4-fbf2-4c09-b577-6bde8fcbdf6e), via openFDA
Source: FDA drug label (Envarsus Xr, NDA206406), Veloxis Pharmaceuticals, Inc, effective February 26, 2025 (SPL set de2315b0-6344-43ac-9aea-3e3b68d828e7), via openFDA
Source: FDA drug label (Tacrolimus), Stellon Biotech Inc., effective July 17, 2026 (SPL set 6b89e8a4-9f11-42e3-8e79-fe617e7c461f), 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
| Nelfinavir | Tacrolimus | |
|---|---|---|
| Labeled for | HIV | Organ transplant rejection, Eczema (atopic dermatitis) |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | n/a | $0.970 per gram 0.1% ointment |
| 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