NutriStack
Fish Oil and Naproxen, a caution.
Naproxen has stronger antiplatelet effects than most NSAIDs. Combined with fish oil's antiplatelet properties, there is additive bleeding risk.
One pair, every claim cited. The two substances, the type, the mechanism, the recommendation, and the primary literature.
Same shape as the other 1,729 pairs in the public database.
From the interaction database
What the row says.
Every entry follows the same shape: what is happening, the mechanism, the recommendation, and the primary literature.
At a glance
- Pair type
- Caution
- Evidence (highest tier)
- Moderate
- Source citations
- 4 sources
- Stack Score effect
- −5 to your Stack Score (per scored caution row).
- Scope
- Supplement × Prescription
- Last verified
- May 30, 2026
Caution · Moderate evidence
Caution
What is happening. Naproxen has stronger antiplatelet effects than most NSAIDs. Combined with fish oil's antiplatelet properties, there is additive bleeding risk.
Mechanism. Naproxen irreversibly inhibits platelet COX-1 for its dosing interval, similar to aspirin. Fish oil EPA reduces thromboxane A2 production. Additive antiplatelet effects increase bleeding risk.
Recommendation. Use moderate fish oil doses (1-2g/day) with caution. Report unusual bruising or GI symptoms.
Sources (4)
- Bays HE. Safety considerations with omega-3 fatty acid therapy. Am J Cardiol. 2007;99(6A):35C-43C. PMID 17368277
- Liao Y, Xie B, Zhang H et al.. Efficacy of omega-3 PUFAs in depression: A meta-analysis.. Translational Psychiatry. 2019. PMID 31383846
- Wei BZ, Li L, Dong CW et al.. The Relationship of Omega-3 Fatty Acids with Dementia and Cognitive Decline: Evidence from Prospective Cohort Studies of Supplementation, Dietary Intake, and Blood Markers.. American Journal of Clinical Nutrition. 2023. PMID 37028557
- Uchida Y, Tsuji K, Ochi E. Effects of Omega-3 fatty acids supplementation and resistance training on skeletal muscle.. Clinical Nutrition ESPEN. 2024. PMID 38777432
Stack Score
How this pair moves the number.
Effect on the composite score
If both Fish Oil and Naproxen are in the same stack, this pair applies −5 to your Stack Score (per scored caution row).
The full algorithm, the clamping rules, and four worked stacks are documented at /methodology/stack-score.
Check your full routine
One pair was the worked example. NutriStack runs every pair in your stack at once.
Drop in your supplements and prescriptions and the public database surfaces every interaction, synergy, timing rule, and contraindication, every one linked to its primary source.