Drug interactions
Mefenamic acid + Naproxen
Severity: Major
Mefenamic acid and Naproxen: major interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Combining two NSAIDs raises the risk of gastrointestinal bleeding and kidney injury without added analgesic benefit. Hyperkalemia and fluid retention are also possible.
What this interaction means in plain words
Mefenamic acid and Naproxen can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Mefenamic acid belongs to Musculoskeletal; Naproxen belongs to Musculoskeletal.
Why it happens
Additive cyclooxygenase inhibition leads to duplicated gastric, platelet and renal effects.
What to do
Avoid using both together and choose a single NSAID at the lowest effective dose. Use gastroprotection if NSAID therapy is needed.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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Other interactions of Naproxen
- Ketorolac intranasal + Naproxen Contraindicated
- Ketorolac + Naproxen Contraindicated
- Aceclofenac + Naproxen Major
- Acemetacin + Naproxen Major
- Acetylsalicylic acid + Naproxen Major
- Alteplase + Naproxen Major
Other interactions of Mefenamic acid
- Ketorolac intranasal + Mefenamic acid Contraindicated
- Ketorolac + Mefenamic acid Contraindicated
- Aceclofenac + Mefenamic acid Major
- Acemetacin + Mefenamic acid Major
- Acetylsalicylic acid + Mefenamic acid Major
- Alteplase + Mefenamic acid Major
Frequently asked questions
Can I take Mefenamic acid with Naproxen?
MediHelp rates the interaction as major. Mefenamic acid and Naproxen can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Combining two NSAIDs raises the risk of gastrointestinal bleeding and kidney injury without added analgesic benefit. Hyperkalemia and fluid retention are also possible.
How serious is the interaction between Mefenamic acid and Naproxen?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid using both together and choose a single NSAID at the lowest effective dose. Use gastroprotection if NSAID therapy is needed.
What other medicines interact with Naproxen?
MediHelp also lists interactions of Naproxen with, for example, Ketorolac intranasal, Ketorolac, Aceclofenac. The full list is on the Naproxen page.
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