What the FDA labels say about taking them together
Allopurinol and obinutuzumab
Obinutuzumab's FDA label of December 19, 2025 names allopurinol in its warnings and precautions section; the allopurinol labels PlainMeds reads (4) do not name obinutuzumab. The obinutuzumab label: “In patients with CLL and NHL at risk for TLS, administer appropriate tumor lysis prophylaxis with anti-hyperuricemics and hydration prior to the infusion of GAZYVA.”
Check it at the source: the allopurinol FDA label on DailyMed (effective May 21, 2026, Rising Pharma Holdings, Inc.); the obinutuzumab FDA label on DailyMed (effective December 19, 2025, Genentech, Inc.).
What does the allopurinol label say about obinutuzumab?
Allopurinol's label (effective May 21, 2026) and its 3 other brand-application labels do not name obinutuzumab in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Allopurinol), Rising Pharma Holdings, Inc., effective May 21, 2026 (SPL set 30ad5ba2-1cef-4933-b104-0597f6a2aaa2), via openFDA; the full label on DailyMed
What does the obinutuzumab label say about allopurinol?
Obinutuzumab label, warnings and precautionsIn patients with CLL and NHL at risk for TLS, administer appropriate tumor lysis prophylaxis with anti-hyperuricemics (e.g., allopurinol or rasburicase) and hydration prior to the infusion of GAZYVA [see Dosage and Administration (2.4) ].
Source: FDA drug label (Gazyva), Genentech, Inc., effective December 19, 2025 (SPL set df12ceb2-5b4b-4ab5-a317-2a36bf2a3cda), 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
| Allopurinol | Obinutuzumab | |
|---|---|---|
| Labeled for | Gout | Leukemia, lymphoma and myeloma |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | $0.0315 per tablet 100 mg tablet | n/a |
| 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