What the FDA labels say about taking them together
Aspirin and mefenamic acid
Mefenamic acid's FDA label of April 20, 2026 names aspirin in its contraindications section; aspirin's label does not name mefenamic acid itself but warns about its class (NSAIDs (nonsteroidal anti-inflammatory drugs)). The mefenamic acid label: “Mefenamic acid and anticoagulants such as warfarin have a synergistic effect on bleeding. The concomitant use of mefenamic acid and anticoagulants have an increased risk of serious bleeding compared to the use of either …”
Check it at the source: the aspirin FDA label on DailyMed (effective September 9, 2025); the mefenamic acid FDA label on DailyMed (effective April 20, 2026, Lupin Pharmaceuticals, Inc.).
What does the aspirin label say about mefenamic acid?
Aspirin's label does not name mefenamic acid 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 mefenamic acid label say about aspirin?
Mefenamic acid label, contraindicationsHistory of asthma, urticaria, or other allergic-type reactions after taking aspirin or other NSAIDs.
Mefenamic acid label, drug interactionsDrugs That Interfere with Hemostasis Clinical Impact: Mefenamic acid and anticoagulants such as warfarin have a synergistic effect on bleeding. The concomitant use of mefenamic acid and anticoagulants have an increased risk of serious bleeding compared to the use of either drug alone. Serotonin release by platelets plays an important role in hemostasis. … Intervention: Monitor patients with concomitant use of mefenamic acid with anticoagulants (e.g., warfarin), antiplatelet agents (e.g., aspirin), selective serotonin reuptake inhibitors (SSRIs), and serotonin norepinephrine reuptake inhibitors (SNRIs) for signs of bleeding [see Warnings and Precautions ()].
Mefenamic acid label, warnings and precautionsMonitor patients with preexisting asthma (without aspirin sensitivity).
Source: FDA drug label (Mefenamic Acid), Lupin Pharmaceuticals, Inc., effective April 20, 2026 (SPL set d15733a9-d5fd-4d5f-86ce-e7ed8c706c7f), 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 | Mefenamic acid | |
|---|---|---|
| Labeled for | Pain, Cough and cold, Fever | Pain |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | $0.0142 per tablet 81 mg tablet | $0.948 per capsule 250 mg capsule |
| 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