What the FDA labels say about taking them together
Foscarnet and tacrolimus
Foscarnet's FDA label of December 11, 2025 names tacrolimus in its drug interactions section; the tacrolimus labels PlainMeds reads (4) do not name foscarnet.
Check it at the source: the foscarnet FDA label on DailyMed (effective December 11, 2025, Clinigen Limited); the tacrolimus FDA label on DailyMed (effective July 17, 2026, Stellon Biotech Inc.).
What does the foscarnet label say about tacrolimus?
Foscarnet label, drug interactionsBecause of foscarnet's tendency to cause renal impairment, the use of FOSCAVIR should be avoided in combination with potentially nephrotoxic drugs such as aminoglycosides, amphotericin B, cyclosporine, acyclovir, methotrexate, tacrolimus and intravenous pentamidine (see above) unless the potential benefits outweigh the risks to the patient.
Source: FDA drug label (Foscavir), Clinigen Limited, effective December 11, 2025 (SPL set 90e3da4e-3b1f-428b-99ca-e4bed1c80028), via openFDA; the full label on DailyMed
What does the tacrolimus label say about foscarnet?
Tacrolimus's label (effective July 17, 2026) and its 3 other brand-application labels do not name foscarnet in these sections. A label lists what its studies and reports found; it is not a complete list.
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
| Foscarnet | 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