Drug & supplement interaction

Fish Oil + Cisplatin

Cisplatin brand name: Platinol-AQ.

Minor Interaction
The bottom line Minor

Fish Oil has a minor interaction with Cisplatin. Theoretically, taking fish oil with platinum agents can cause resistance to platinum agents, potentially decreasing their effectiveness.

Read the full interaction report
SeverityMinor
LikelihoodUnlikely
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Fish Oil and Cisplatin

Here is the interaction we found between these two, with the evidence behind it.

Minor

PLATINUM AGENTS

Why this applies to Cisplatin

Cisplatin falls under PLATINUM AGENTS — the group Fish Oil interacts with.

Theoretically, taking fish oil with platinum agents can cause resistance to platinum agents, potentially decreasing their effectiveness.
Platinum-induced fatty acids (PIFAs) are fatty acids secreted from human and mouse stem cells when exposed to platinum-based chemotherapy. Animal research suggests that PIFAs cause resistance to chemotherapy by stimulating lysophospholipid production in the spleen, which interferes with the DNA damage caused by certain chemotherapy drugs. One PIFA, known as 16:4(n-3), has been found in both raw fish and some commercially available fish oil products. Mackerel and herring have high PIFA concentrations, while salmon and tuna have low PIFA concentrations. Levels of PIFA in commercial fish oil products ranged from 0.2- 5.7 microMol. Animal research shows that PIFA-containing fish oil products cause resistance to cisplatin, fluorouracil, irinotecan, and oxaliplatin. It is unclear if all commercially available fish oil products contain PIFAs. Additionally, it is argued that levels of PIFA found in some fish oil products are too low to be of clinical concern. Furthermore, a lack of chemotherapy resistance in countries with high fish intake, such as Greenland, Japan, and Norway, suggest that this interaction may not be clinically significant.
Severity Minor Likelihood Unlikely Evidence D

Interaction has been demonstrated in animal or in lab research but has been shown not to occur in humans..

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the concern people raise with fish oil during cisplatin treatment. Some fish and certain fish oil products contain a fatty acid called 16:4(n-3), one of a group nicknamed PIFAs. In animal studies, these fatty acids seemed to help cancer cells resist chemo, which could in theory make cisplatin work less well against your tumor. So the worry here is reduced benefit, not more side effects.

I want to be straight with you though: this is theoretical and based only on lab and animal research. Many experts feel the amounts in supplements are likely too low to matter, and countries that eat lots of fish don't show worse chemo results. Still, while you're on cisplatin, the safest move is to clear any fish oil supplement with your oncology team first so nothing competes with your treatment.

References
  1. Daenen LG, Cirkel GA, Houthuijzen JM, et al. Increased plasma levels of chemoresistance-inducing fatty acid 16:4(n-3) after consumption of fish and fish oil. JAMA Oncol 2015;1(3):350-8. PubMed
  2. Mazurak VC, Calder PC, van der Meij BS. Let them eat fish. JAMA Oncol 2015;1(6):840.
  3. Baracos V. Let them eat fish. JAMA Oncol 2015;1(6):840-1.
  4. Roodhart JM, Daenen LG, Stigter EC, et al. Mesenchymal stem cells induce resistance to chemotherapy through the release of platinum-induced fatty acids. Cancer Cell 2011;20(3):370-83.
  5. Houthuijzen JM, Daenen LG, Roodhart JM, et al. Lysophospholipids secreted by splenic macrophages induce chemotherapy resistance via interference with the DNA damage response. Nat Commun 2014;5:5275. PubMed

What These Ratings Mean

Every interaction above is graded three ways — here’s the key to each label.

Severity how clinically significant the interaction is
Major

Clinically significant. Avoid the combination, or use only under close professional supervision.

Moderate

Usually worth avoiding or managing — may need monitoring, a dose change, or timing apart.

Minor

Generally not serious. Be aware of it and mention it to your pharmacist.

Likelihood how strong the evidence is that the interaction actually happens in people
  • LikelyWell-controlled human studies have demonstrated the likely existence of this interaction.
  • ProbableInteraction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
  • PossibleInteraction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.
  • UnlikelyInteraction has been demonstrated in animal or in lab research but has been shown not to occur in humans.
Evidence the quality of the studies behind the rating (graded A–D)
  • AHigh-quality meta-analysis (quantitative systematic review).
  • BCase-control study.
  • CConsensus.
  • DAnecdotal evidence.

These ratings are for information only. Never start, stop, or otherwise change your therapy before speaking with your provider.

Keep it in perspective

Fish Oil Also Interacts With Other Medications

Fish Oil has 207 moderate, 119 minor known drug interactions in our database — the Cisplatin one above is one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Fish Oil

Covers the 2,830 medications we’ve checked against Fish Oil. Pick one to open its full report.

From our Q&A

Questions About Fish Oil or Cisplatin

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Fish Oil or Cisplatin, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Cisplatin

This page covers Fish Oil only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Cisplatin page lists 90 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Asarabacca (major), Siberian Cocklebur (major), Acerola (moderate) and Active Hexose Correlated Compound (ahcc) (moderate).

By severity: 3 major · 75 moderate · 12 minor.

From our pharmacist’s overview on the Cisplatin page

“Kidney damage is the risk I would flag first for anyone receiving cisplatin (Platinol-AQ). Cisplatin is a chemotherapy drug that already stresses the kidneys, and two of the three major-rated interactions on this list, Siberian cocklebur and asarabacca, involve herbs that can injure the kidneys on their own, stacking harm on an organ t…”

Reviewed by 2 · Jul 18, 2026

Open the Cisplatin interaction page

One more smart check

Taking Fish Oil as Part of a Dietary Supplement Product? Check It for Interactions

We hold 4,777 real supplement products containing Fish Oil, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Fish Oil. Your product may carry other ingredients that interact with Cisplatin too, on top of Fish Oil — and those would not show on this page. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Fish Oil and Cisplatin Sit Against Everything Else

Out of every supplement and medication people look up on HelloPharmacist, here is where these two land this week — and which way each has been moving.

Supplement Fish Oil
Top 5%

#62 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Cisplatin
Top half

#1,396 of 2,830 medications looked up here in the last 7 days

29 days ago today

Position among everything looked up on this site, not a measure of how commonly either one is used or how important it is. A supplement can climb this list because of a news story. It counts every request to the page, automated ones included, and nothing here identifies anyone.

Supplement

About Fish Oil

What is Fish Oil?

Fish Oil
  • High triglycerides
  • Heart health
  • Joint pain and inflammation
  • Brain and eye health
  • Dry eyes

Fish oil provides omega-3 fatty acids (EPA and DHA) that are best known for lowering high triglyceride levels. The evidence for other heart and health benefits is mixed, and it is generally well tolerated. Talk with your pharmacist or doctor before starting it, especially if you take blood thinners or have a fish allergy.

Read the full Fish Oil monograph & all interactions
Medication

About Cisplatin Injection

What Is Cisplatin Injection Used For?

Brand name: Platinol-AQ

Cisplatin Injection is used to treat three types of cancer. For metastatic testicular tumors and metastatic ovarian tumors, it is used as part of combination chemotherapy — alongside other approved cancer medicines — in patients who have already had surgery and/or radiation therapy. For metastatic ovarian tumors, it can also be used alone as a second-line treatment when standard chemotherapy has stopped working and cisplatin has not been tried before.

For advanced bladder cancer (specifically transitional cell bladder cancer) that can no longer be treated with surgery or radiation, Cisplatin Injection is used as a single agent.

See full Cisplatin Injection drug information
Keep checking

Other Drugs & Fish Oil

Browse every other medication we’ve checked against Fish Oil — both the ones with a known interaction and the ones without. Select any drug for the full detail.

0Major
207Moderate
119Minor
2,503No known interaction
Moderate

207 interactions

Showing 60 of 207 moderate interactions — see all 207 on the Fish Oil page.

Minor

119 interactions

Showing 60 of 119 minor interactions — see all 119 on the Fish Oil page.

No interaction 2,503 drugs checked — show the list
Sources

Sources & How We Checked

Interaction details are evidence-graded and sourced from the Natural Medicines database. The medication overview comes from MedlinePlus.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

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Pharmacist Counseling Corner

Taking Fish Oil and Cisplatin Together: Common Questions

Can you take Fish Oil with Cisplatin?
There is only a minor interaction, which is usually not serious. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Fish Oil and Cisplatin interaction?
We rate it Minor. This interaction is generally not clinically significant, but it remains worth noting and discussing with your pharmacist.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Still Have a Question About Cisplatin and Fish Oil?

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This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.