NutriStack
Aspirin Low-Dose and Fish Oil, a caution.
Fish oil has antiplatelet properties that add to aspirin's cyclooxygenase inhibition, potentially increasing bleeding risk. While the combination is sometimes used therapeutically for cardiovascular benefit, the additive antiplatelet effect requires awareness of increased bleeding potential.
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
- Substances
- Aspirin Low-Dose and Fish Oil
- 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. Fish oil has antiplatelet properties that add to aspirin's cyclooxygenase inhibition, potentially increasing bleeding risk. While the combination is sometimes used therapeutically for cardiovascular benefit, the additive antiplatelet effect requires awareness of increased bleeding potential.
Mechanism. Aspirin irreversibly inhibits COX-1, reducing thromboxane A2 production. Fish oil's EPA/DHA compete with arachidonic acid for COX enzymes, producing less potent thromboxane A3 and further reducing platelet aggregation. The combined effect creates greater antiplatelet activity.
Recommendation. Low-dose fish oil (1-2g/day) with low-dose aspirin is often considered acceptable for cardiovascular benefit, but monitor for increased bruising or bleeding. Higher fish oil doses (>3g/day) further increase bleeding risk. Discuss with your cardiologist.
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 Aspirin Low-Dose and Fish Oil 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.