What the FDA labels say about taking them together
Potassium chloride and tacrolimus
Potassium chloride's FDA label (Potassium Chloride) of January 9, 2026 names tacrolimus in its drug interactions section; the tacrolimus labels PlainMeds reads (4) do not name potassium chloride. The potassium chloride label: “Drug Interactions Other Products that Cause Hyperkalemia Administration of Potassium Chloride Injection in patients treated concurrently or recently with other products that can cause hyperkalemia or increase the risk …”
Check it at the source: the potassium chloride FDA label on DailyMed (effective July 14, 2025, Upsher-Smith Laboratories, LLC); the tacrolimus FDA label on DailyMed (effective July 17, 2026, Stellon Biotech Inc.).
What does the potassium chloride label say about tacrolimus?
Potassium Chloride label (Baxter Healthcare Corporation, January 9, 2026), drug interactionsDrug Interactions Other Products that Cause Hyperkalemia Administration of Potassium Chloride Injection in patients treated concurrently or recently with other products that can cause hyperkalemia or increase the risk of hyperkalemia (e.g., potassium-sparing diuretics, ACE inhibitors, angiotensin II receptor antagonists, cyclosporine and tacrolimus) increases the risk of severe and potentially fatal hyperkalemia, in particular in the presence of other risk factors for hyperkalemia (see WARNINGS ).
Source: FDA drug label (Potassium Chloride, NDA019904), Baxter Healthcare Corporation, effective January 9, 2026 (SPL set 092ddee4-572d-4771-8d95-880cea01097e), via openFDA
Source: FDA drug label (KLOR-CON M), Upsher-Smith Laboratories, LLC, effective July 14, 2025 (SPL set b89910f6-4ff5-4a62-8269-696f7c10e4f6), via openFDA; the full label on DailyMed
What does the tacrolimus label say about potassium chloride?
Tacrolimus's label (effective July 17, 2026) and its 3 other brand-application labels do not name potassium chloride 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
| Potassium chloride | Tacrolimus | |
|---|---|---|
| Labeled for | n/a | Organ transplant rejection, Eczema (atopic dermatitis) |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | $0.0828 per tablet 10 mEq tablet | $0.970 per gram 0.1% ointment |
| 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