What the FDA labels say about taking them together
Allopurinol and pegloticase
Allopurinol's FDA label of May 21, 2026 names pegloticase in its drug interactions section; the pegloticase label PlainMeds reads does not name allopurinol. The allopurinol label: “Clinical Impact; Concomitant use of allopurinol and pegloticase may potentially blunt the rise of serum uric acid levels and increase the risk of pegloticase related anaphylaxis in patients whose uric acid level …”
Check it at the source: the allopurinol FDA label on DailyMed (effective May 21, 2026, Rising Pharma Holdings, Inc.); the pegloticase FDA label on DailyMed (effective July 9, 2026, Horizon Therapeutics USA, Inc.).
What does the allopurinol label say about pegloticase?
Allopurinol label, drug interactionsClinical Impact; Concomitant use of allopurinol tablets and pegloticase may potentially blunt the rise of serum uric acid levels and increase the risk of pegloticase related anaphylaxis in patients whose uric acid level increase to above 6 mg/dL.
Source: FDA drug label (Aloprim, NDA020298), Mylan Institutional LLC, effective February 18, 2022 (SPL set 10cc918f-aa44-415b-932d-2404695ac449), via openFDA
Source: FDA drug label (Allopurinol, NDA018832), Actavis Pharma, Inc., effective April 1, 2024 (SPL set a80fe56f-8d03-423f-8e2a-7ec8c9e5045b), via openFDA
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 pegloticase label say about allopurinol?
Pegloticase's label (effective July 9, 2026) does not name allopurinol in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Krystexxa), Horizon Therapeutics USA, Inc., effective July 9, 2026 (SPL set 6e566303-d93a-4130-b764-25749829aa95), 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 | Pegloticase | |
|---|---|---|
| Labeled for | Gout | Gout |
| 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