Drug & supplement interaction

Safflower + Diclofenac Sodium

Diclofenac Sodium brand names: Voltaren XR, Voltaren, Voltaren SR, Diclo, Difenac, and others.

Moderate Interaction
Medically reviewed by · Updated September 2026
The bottom line Moderate

Safflower has a moderate interaction with Diclofenac Sodium. High doses of safflower oil might increase the risk of bleeding when taken with anticoagulant or antiplatelet drugs.

Read the full interaction report
SeverityModerate
LikelihoodPossible
EvidenceB
What do Severity, Likelihood & Evidence mean?
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Interaction report

Safflower and Diclofenac Sodium

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

Moderate

ANTICOAGULANT/ANTIPLATELET DRUGS

Why this applies to Diclofenac Sodium

Diclofenac Sodium falls under ANTICOAGULANT/ANTIPLATELET DRUGS — the group Safflower interacts with.

High doses of safflower oil might increase the risk of bleeding when taken with anticoagulant or antiplatelet drugs.
Small clinical studies show that taking safflower oil, approximately 55 grams daily for 2-3 weeks, decreases platelet aggregation. However, taking lower doses of safflower oil, such as 5 grams daily for 4 weeks, does not seem to affect platelet function. In one case report, a 74-year-old male stabilized on warfarin developed urinary tract bleeding and an elevated INR after taking a safflower extract 20 grams daily for 14 days.
Severity Moderate Likelihood Possible Evidence B

Interaction 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.

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

Here's the simple version: Diclofenac is an NSAID, and like other anti-inflammatory pain relievers it can irritate the stomach lining and make it harder for your blood to clot normally. Safflower comes into play because high doses of safflower oil (think concentrated supplements, around 55 grams a day) have been shown to make platelets a little less sticky. Stack that on top of diclofenac and you may nudge your bleeding risk up a notch.

What that could look like in real life: easier bruising, nosebleeds, dark or bloody stools, or stomach upset that lingers. The good news is that normal cooking with safflower oil, or low doses like 5 grams daily, doesn't seem to bother platelets at all. The concern is really with big supplement doses. If you're considering a safflower supplement while on diclofenac, check with your pharmacist or doctor first.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Demke, D. M., Peters, G. R., Linet, O. I., Metzler, C. M., and Klott, K. A. Effects of a fish oil concentrate in patients with hypercholesterolemia. Atherosclerosis 1988;70(1-2):73-80. PubMed
  2. Kwon, J. S., Snook, J. T., Wardlaw, G. M., and Hwang, D. H. Effects of diets high in saturated fatty acids, canola oil, or safflower oil on platelet function, thromboxane B2 formation, and fatty acid composition of platelet phospholipids. Am.J.Clin.Nutr. PubMed
  3. Challen, A. D., Branch, W. J., and Cummings, J. H. The effect of aspirin and linoleic acid on platelet aggregation, platelet fatty acid composition and haemostasis in man. Hum Nutr Clin Nutr 1983;37(3):197-208.
  4. Liu Y, Liu S, Shi Y, et al. Effects of safflower injection on the pharmacodynamics and pharmacokinetics of warfarin in rats. Xenobiotica. 2017 Oct 25:1-6. [Epub ahead of print] 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

Safflower Also Interacts With Other Medications

Safflower has 207 moderate known drug interactions in our database — the Diclofenac Sodium one above is one of them. If you take anything else, check it against the full list below.

Moderate 207 No known interaction 2,623 (incl. Diclofenac Sodium)
Taking anything else?

Check Another of Your Medications Against Safflower

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

From our Q&A

Questions About Safflower or Diclofenac Sodium

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Safflower or Diclofenac Sodium, 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 Diclofenac Sodium

This page covers Safflower only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Diclofenac Sodium page lists 308 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Asarabacca (major), Beer (major), Danshen (major) and Piracetam (major).

By severity: 7 major · 266 moderate · 35 minor.

From our pharmacist’s overview on the Diclofenac Sodium page

“Diclofenac (Voltaren), a daily mainstay for arthritis and joint pain, comes with a supplement list that calls for real vigilance. Of the 308 ingredients on file, 7 rate major, and roughly two hundred entries share a single theme: anything with blood-thinning activity adds to diclofenac's own bleeding risk, especially in the stomach.”

Reviewed by 2 · Jul 18, 2026

Open the Diclofenac Sodium interaction page

One more smart check

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

We hold 276 real supplement products containing Safflower, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Safflower. Your product may carry other ingredients that interact with Diclofenac Sodium too, on top of Safflower — 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 Safflower and Diclofenac Sodium 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 Safflower
Top half

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

29 days ago today
Medication Diclofenac Sodium
Top 25%

#350 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 Safflower

What is Safflower?

Safflower
  • Heart and cholesterol support
  • Skin moisturizing
  • Menstrual cramps
  • Mild constipation
  • Weight management (oil)

Safflower is a thistle-like plant used mainly for its seed oil (a common cooking oil) and its colorful flowers. Safflower oil is a reasonable source of unsaturated fats, but strong proof that supplements treat specific diseases is limited. The flower extracts have much weaker evidence and should be used with caution, especially during pregnancy.

Read the full Safflower monograph & all interactions
Medication

About Diclofenac

What Is Diclofenac Used For?

Brand names: Voltaren XR, Voltaren, Voltaren SR, Diclo, Difenac, Diclo SR, Voltarol, Acoflam, Defenac, Dicloflex, Diclovol, Diclozip, Fenactol, Flamrase, Volraman, Diclomax SR, Diclomax Retard, Motifene 75 mg, Voltarol 75 mg SR, Acoflam 75 SR, Defenac SR, Dexomon 75 SR, Dicloflex 75 SR, Diclovol SR, Fenactol 75 mg SR, Flamatak 75 MR, Flamrase SR, Flexotard MR 75, Rheumatac Retard 75, Rhumalgan CR, Slofenac SR, Volsaid Retard 75, Voltarol Retard, Acoflam Retard, Defenac Retard, Dexomon Retard 100, Dicloflex Retard, Diclovol Retard, Fenactol Retard 100 mg, Flamatak 100 MR, Volsaid Retard 100, Voltarol Ophtha Multidose, Voltarol Ophtha, Pennsaid, Voltaren Emulgel, Dyloject

Diclofenac sodium topical gel is used to treat actinic keratoses (AK) — rough, scaly skin patches that form after years of sun exposure. These patches are considered precancerous, meaning they can develop into skin cancer if left untreated.

This is a topical gel, meaning it is applied directly to the skin over the affected area rather than taken by mouth. It belongs to the NSAID (nonsteroidal anti-inflammatory drug) family.

See full Diclofenac drug information
Keep checking

Other Drugs & Safflower

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

0Major
207Moderate
0Minor
2,622No known interaction
207 Moderate 2,622 No interaction
Moderate

207 interactions

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

No interaction 2,622 drugs checked — show the list

We also checked Safflower against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 2,622 medications checked with no known interaction — see the full Safflower list.

See the full Safflower interactions page
See every supplement checked against Diclofenac Sodium, ranked by severity
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

Keep exploring
Safflower monograph › Uses, safety, and every drug interaction in one place Diclofenac Sodium supplement interactions › Every supplement checked against Diclofenac Sodium, ranked by severity Diclofenac drug information › The full plain-English guide to this medication Supplement interaction checker › Check any supplement or product against your medications Browse medications A–Z › Every drug we've checked against herbs & supplements Ask a pharmacist › Free, personal answer from our licensed team
Pharmacist Counseling Corner

Taking Safflower and Diclofenac Sodium Together: Common Questions

Can you take Safflower with Diclofenac Sodium?
There is a moderate interaction, so it may be acceptable with monitoring or timing changes — but check with your pharmacist first. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Safflower and Diclofenac Sodium interaction?
We rate it Moderate. This combination may require monitoring, a dose adjustment, or separating the times you take each one. Consult your pharmacist before using them together.

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

Still Have a Question About Diclofenac Sodium and Safflower?

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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.