What the FDA labels say about taking them together
Chloramphenicol and tacrolimus
Tacrolimus's FDA label of July 17, 2026 names chloramphenicol in its drug interactions section; the chloramphenicol label PlainMeds reads does not name tacrolimus. The tacrolimus label: “Reduce PROGRAF dose and adjust dose based on tacrolimus whole blood trough concentrations. Early and frequent monitoring of tacrolimus whole blood trough levels should start within 1-3 days and continue monitoring as …”
Check it at the source: the chloramphenicol FDA label on DailyMed (effective October 10, 2024, Fresenius Kabi USA, LLC); the tacrolimus FDA label on DailyMed (effective July 17, 2026, Stellon Biotech Inc.).
What does the chloramphenicol label say about tacrolimus?
Chloramphenicol's label (effective October 10, 2024) does not name tacrolimus in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Chloramphenicol Sodium Succinate), Fresenius Kabi USA, LLC, effective October 10, 2024 (SPL set aed29594-211d-49ef-813f-131975a8d0e3), via openFDA; the full label on DailyMed
What does the tacrolimus label say about chloramphenicol?
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,,)].; …
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
| Chloramphenicol | Tacrolimus | |
|---|---|---|
| Labeled for | n/a | Organ transplant rejection, Eczema (atopic dermatitis) |
| Boxed warning | Yes | 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