What the FDA labels say about taking them together
Aspirin and diflunisal
Diflunisal's FDA label of August 4, 2026 names aspirin in its contraindications section; aspirin's label does not name diflunisal itself but warns about its class (NSAIDs (nonsteroidal anti-inflammatory drugs)). The diflunisal label: “Aspirin When diflunisal is administered with aspirin, its protein binding is reduced, although the clearance of free diflunisal is not altered.”
Check it at the source: the aspirin FDA label on DailyMed (effective September 9, 2025); the diflunisal FDA label on DailyMed (effective August 4, 2026, Heritage Pharmaceuticals Inc. d/b/a Avet Pharmaceuticals Inc.).
What does the aspirin label say about diflunisal?
Aspirin's label does not name diflunisal itself; it warns about its class (NSAIDs (nonsteroidal anti-inflammatory drugs)):
Aspirin label, warningsThis product contains an NSAID, which may cause severe stomach bleeding.
Aspirin label, warningsThe chance is higher if you: are age 60 or older have had stomach ulcers or bleeding problems take a blood thinning (anticoagulant) or steroid drug take other drugs containing prescription or nonprescription NSAIDs (aspirin, ibuprofen, naproxen, or others) have 3 or more alcohol drinks every day while using this product take more or for a longer time than directed
Source: FDA drug label (Medique Products Aspirin), Unifirst First Aid Corporation, effective September 9, 2025 (SPL set 9b28fed0-a993-ca72-e053-2995a90ac7fd), via openFDA; the full label on DailyMed
What does the diflunisal label say about aspirin?
Diflunisal label, contraindicationsDiflunisal tablets should not be given to patients who have experienced asthma, urticaria, or allergic-type reactions after taking aspirin or other NSAIDs.
Diflunisal label, drug interactionsAspirin When diflunisal is administered with aspirin, its protein binding is reduced, although the clearance of free diflunisal is not altered.
Diflunisal label, warningsThere is no consistent evidence that concurrent use of aspirin mitigates the increased risk of serious CV thrombotic events associated with NSAID use.
Source: FDA drug label (diflunisal), Heritage Pharmaceuticals Inc. d/b/a Avet Pharmaceuticals Inc., effective August 4, 2026 (SPL set 666f89b4-fd81-420a-a390-eb1cd4014f61), 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
| Aspirin | Diflunisal | |
|---|---|---|
| Labeled for | Pain, Cough and cold, Fever | Pain, Osteoarthritis, Rheumatoid arthritis |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | $0.0142 per tablet 81 mg tablet | $1.06 per tablet 500 mg tablet |
| 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