What the FDA labels say about taking them together
Sirolimus and spironolactone
Spironolactone's FDA label (Spironolactone) of August 28, 2026 names sirolimus in its drug interactions section; the sirolimus labels PlainMeds reads (4) do not name spironolactone. The spironolactone label: “Dosage adjustments of the drugs metabolized by CYP2C8 (e.g., repaglinide) and CYP3A4/5 may be necessary if they are given concurrently with spironolactone.”
Check it at the source: the sirolimus FDA label on DailyMed (effective January 28, 2026, Glenmark Pharmaceuticals Inc., USA); the spironolactone FDA label on DailyMed (effective November 28, 2025, Pfizer Laboratories Div Pfizer Inc).
What does the sirolimus label say about spironolactone?
Sirolimus's label (effective January 28, 2026) and its 3 other brand-application labels do not name spironolactone in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (sirolimus), Glenmark Pharmaceuticals Inc., USA, effective January 28, 2026 (SPL set 57fb4d90-3ccb-4a69-af1e-53be83f7a504), via openFDA; the full label on DailyMed
What does the spironolactone label say about sirolimus?
Spironolactone label (Atlantic Biologicals Corp., August 28, 2026), drug interactionsDosage adjustments of the drugs metabolized by CYP2C8 (e.g., repaglinide) and CYP3A4/5 (e.g., midazolam, sirolimus and tacrolimus) may be necessary if they are given concurrently with spironolactone.
Source: FDA drug label (Spironolactone, NDA209478), Atlantic Biologicals Corp., effective August 28, 2026 (SPL set 5a203ae4-0ed1-0099-e063-6294a90abc85), via openFDA
Source: FDA drug label (Aldactone), Pfizer Laboratories Div Pfizer Inc, effective November 28, 2025 (SPL set 0fed2822-3a03-4b64-9857-c682fcd462bc), 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
| Sirolimus | Spironolactone | |
|---|---|---|
| Labeled for | Organ transplant rejection | Heart failure, Edema (fluid retention), High blood pressure |
| Boxed warning | Yes | No |
| Pharmacy cost (NADAC) | $0.723 per tablet 1 mg tablet | $0.0426 per tablet 25 mg tablet |
| Shortage now | No current entry | A presentation being discontinued |
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