What the FDA labels say about taking them together
Nelarabine and pentostatin
Nelarabine's FDA label of March 31, 2025 names pentostatin in its drug interactions section; the pentostatin label PlainMeds reads does not name nelarabine. The nelarabine label: “DRUG INTERACTIONS Administration of ARRANON in combination with adenosine deaminase (ADA) inhibitors, such as pentostatin, is not recommended.”
Check it at the source: the nelarabine FDA label on DailyMed (effective March 31, 2025, Sandoz Inc); the pentostatin FDA label on DailyMed (effective July 1, 2026, Hospira, Inc.).
What does the nelarabine label say about pentostatin?
Nelarabine label, drug interactionsDRUG INTERACTIONS Administration of ARRANON in combination with adenosine deaminase (ADA) inhibitors, such as pentostatin, is not recommended [see Clinical Pharmacology (12.3)].
Source: FDA drug label (Arranon), Sandoz Inc, effective March 31, 2025 (SPL set 0f9051de-5c4d-4c0f-8c19-e15214498cca), via openFDA; the full label on DailyMed
What does the pentostatin label say about nelarabine?
Pentostatin's label (effective July 1, 2026) does not name nelarabine in these sections. A label lists what its studies and reports found; it is not a complete list.
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
| Nelarabine | 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