What the FDA labels say about taking them together
Fludarabine and pentostatin
Fludarabine's FDA label of October 14, 2024 names pentostatin in its boxed warning section, and pentostatin's label names fludarabine too. The pentostatin label: “The combined use of NIPENT and fludarabine phosphate is not recommended because it may be associated with an increased risk of fatal pulmonary toxicity (see WARNINGS ).”
Check it at the source: the fludarabine FDA label on DailyMed (effective October 14, 2024, Fresenius Kabi USA, LLC); the pentostatin FDA label on DailyMed (effective July 1, 2026, Hospira, Inc.).
What does the fludarabine label say about pentostatin?
Fludarabine label, boxed warningIn a clinical investigation using fludarabine in combination with pentostatin (deoxycoformycin) for the treatment of refractory chronic lymphocytic leukemia (CLL), there was an unacceptably high incidence of fatal pulmonary toxicity.
Source: FDA drug label (Fludarabine), Fresenius Kabi USA, LLC, effective October 14, 2024 (SPL set cf5255cc-91fd-4132-973b-764dba142eae), via openFDA; the full label on DailyMed
What does the pentostatin label say about fludarabine?
Pentostatin label, boxed warningIn a clinical investigation in patients with refractory chronic lymphocytic leukemia using NIPENT at the recommended dose in combination with fludarabine phosphate, 4 of 6 patients entered in the study had severe or fatal pulmonary toxicity.
Pentostatin label, drug interactionsThe combined use of NIPENT and fludarabine phosphate is not recommended because it may be associated with an increased risk of fatal pulmonary toxicity (see WARNINGS ).
Source: FDA drug label (Nipent), Hospira, Inc., effective July 1, 2026 (SPL set 674e0e6d-46ed-4868-9196-04019d667716), 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
| Fludarabine | Pentostatin | |
|---|---|---|
| Labeled for | Leukemia, lymphoma and myeloma | Leukemia, lymphoma and myeloma |
| Boxed warning | Yes | Yes |
| Pharmacy cost (NADAC) | n/a | n/a |
| Shortage now | No current entry | In shortage |
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