What the FDA labels say about taking them together
Fentanyl and palbociclib
Palbociclib's FDA label of July 2, 2026 names fentanyl in its drug interactions section; the fentanyl labels PlainMeds reads (2) do not name palbociclib. The palbociclib label: “The dose of the sensitive CYP3A substrate with a narrow therapeutic index may need to be reduced, as IBRANCE may increase its exposure.”
Check it at the source: the fentanyl FDA label on DailyMed (effective March 6, 2026, Hikma Pharmaceuticals USA Inc.); the palbociclib FDA label on DailyMed (effective July 2, 2026, Pfizer Laboratories Div Pfizer Inc).
What does the fentanyl label say about palbociclib?
Fentanyl's label (effective March 6, 2026) and its 1 other brand-application label do not name palbociclib in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Fentanyl Citrate), Hikma Pharmaceuticals USA Inc., effective March 6, 2026 (SPL set ce5db1c2-feb1-4ad2-847a-d02e865bd47e), via openFDA; the full label on DailyMed
What does the palbociclib label say about fentanyl?
Palbociclib label, drug interactionsThe dose of the sensitive CYP3A substrate with a narrow therapeutic index (e.g., alfentanil, cyclosporine, dihydroergotamine, ergotamine, everolimus, fentanyl, pimozide, quinidine, sirolimus, and tacrolimus) may need to be reduced, as IBRANCE may increase its exposure [see Clinical Pharmacology (12.3) ].
Source: FDA drug label (Ibrance), Pfizer Laboratories Div Pfizer Inc, effective July 2, 2026 (SPL set fecbdd7d-b729-41b5-9872-231b8fe104ce), 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
| Fentanyl | Palbociclib | |
|---|---|---|
| Labeled for | Pain | Breast cancer |
| Boxed warning | Yes | No |
| Pharmacy cost (NADAC) | $1.79 per mL 100 mcg/2 mL vial | n/a |
| Shortage now | In shortage | 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