Drug & supplement interaction

Evening Primrose + Naproxen, Sumatriptan

Naproxen, Sumatriptan brand name: Treximet.

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

Naproxen, Sumatriptan falls into 2 drug categories that Evening Primrose can interact with; the most serious is rated moderate. Theoretically, evening primrose oil may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.

Read the full interaction report
SeverityModerate
LikelihoodPossible
Interactions2
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Evening Primrose and Naproxen, Sumatriptan

These two interact in 2 distinct ways. Each one is explained separately below.

Why Are There 2 Interactions?

Evening Primrose interacts with whole categories of medication. Naproxen, Sumatriptan falls into 2 of those categories, so it can interact with Evening Primrose in 2 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Moderate).

Moderate

ANTICOAGULANT/ANTIPLATELET DRUGS

1 of 2

Why this applies to Naproxen, Sumatriptan

Naproxen, Sumatriptan falls under ANTICOAGULANT/ANTIPLATELET DRUGS — the group Evening Primrose interacts with.

Theoretically, evening primrose oil may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Evening primrose oil contains gamma linolenic acid (GLA). There is preliminary clinical evidence that GLA can reduce platelet aggregation and prolong bleeding time.
Severity Moderate Likelihood Possible Evidence D

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

Treximet pairs naproxen (an NSAID) with sumatriptan (a migraine medicine). The piece that matters here is naproxen, because NSAIDs already make platelets a little less sticky, which can nudge up your bleeding risk. Evening primrose oil contains GLA, and there's some early, mostly theoretical evidence that it may also slow platelets down and lengthen bleeding time.

Put the two together and you could, in theory, see things like easier bruising, nosebleeds, or stomach irritation that lingers a bit longer. To be clear, this is a possible, lab-based concern, not something firmly proven in people. Still, it's worth a quick chat with your pharmacist or doctor before combining them, especially if you take blood thinners, have a bleeding problem, or have surgery coming up.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Guivernau M, Meza N, Barja P, Roman O. Clinical and experimental study on the long-term effect of dietary gamma-linolenic acid on plasma lipids, platelet aggregation, thromboxane formation, and prostacyclin production. Prostaglandins Leukot Essent Fatty A PubMed
Minor

CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES

2 of 2

Naproxen, Sumatriptan also falls under CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES.

Theoretically, evening primrose may increase the levels and clinical effects of CYP2C9 substrates.
In vitro research shows that linoleic acid, a constituent of evening primrose oil, inhibits CYP2C9.
Severity Minor Likelihood Possible Evidence D

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

Treximet combines naproxen (an NSAID) with sumatriptan for migraines. The naproxen part is partly cleared by a liver enzyme called CYP2C9. Lab studies hint that a fatty acid in evening primrose oil might gently slow that enzyme down, which could in theory let a little more naproxen build up in your system.

If that happened, you might notice more of naproxen's usual side effects, like stomach upset, heartburn, or, with long-term use, a higher risk of bleeding. Keep in mind evening primrose itself can also nudge bleeding risk slightly. Honestly, though, this is only a theoretical concern from test-tube data, and the rating is minor. It's not something I'd lose sleep over, but do mention both to your pharmacist, especially if you have a bleeding problem.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Zou L, Harkey MR, and Henderson GL. Effects of herbal components on cDNA-expressed cytochrome P450 enzyme catalytic activity. Life Sci 8-16-2002;71(13):1579-1589. 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

Evening Primrose Also Interacts With Other Medications

Evening Primrose has 147 moderate, 85 minor known drug interactions in our database — the Naproxen, Sumatriptan one above is among them. If you take anything else, check it against the full list below.

Moderate 147 Minor 85 No known interaction 2,598 (incl. Naproxen, Sumatriptan)
Taking anything else?

Check Another of Your Medications Against Evening Primrose

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

Everything else you take

See Every Supplement That Interacts With Naproxen, Sumatriptan

This page covers Evening Primrose only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Naproxen, Sumatriptan page lists 332 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), American Hellebore (major), Arsenic (major), Asarabacca (major) and Beer (major).

By severity: 14 major · 273 moderate · 45 minor.

From our pharmacist’s overview on the Naproxen, Sumatriptan page

“Treximet combines naproxen, an anti-inflammatory painkiller, with sumatriptan for migraine, and that pairing gives its interaction list real teeth. Of the 332 supplements and herbs on file, 14 carry a major rating, and those are the entries to understand first.”

Reviewed by 2 · Jul 18, 2026

Open the Naproxen, Sumatriptan interaction page

One more smart check

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

We hold 98 real supplement products containing Evening Primrose, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Evening Primrose. Your product may carry other ingredients that interact with Naproxen, Sumatriptan too, on top of Evening Primrose — 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 Evening Primrose and Naproxen, Sumatriptan 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 Evening Primrose
Top half

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

29 days ago today
Medication Naproxen, Sumatriptan
Steady interest

#2,091 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 Evening Primrose

What is Evening Primrose?

Evening Primrose
  • Eczema and skin health
  • PMS symptoms
  • Breast pain (mastalgia)
  • Menopause symptoms
  • Inflammation
  • Diabetic nerve pain

Evening primrose oil is a seed oil rich in gamma-linolenic acid (GLA), an omega-6 fatty acid, that is popularly used for skin conditions, PMS, and breast pain. The evidence behind most of these uses is mixed or weak, and it is not proven to be a reliable treatment for any condition. It is generally well tolerated for short-term use, but talk to your pharmacist or doctor before starting it, especially if you are pregnant or have a bleeding disorder.

Read the full Evening Primrose monograph & all interactions
Keep checking

Other Drugs & Evening Primrose

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

0Major
147Moderate
85Minor
2,597No known interaction
147 Moderate 85 Minor 2,597 No interaction
Moderate

147 interactions

Showing 60 of 147 moderate interactions — see all 147 on the Evening Primrose page.

Minor

85 interactions

Showing 60 of 85 minor interactions — see all 85 on the Evening Primrose page.

No interaction 2,597 drugs checked — show the list

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

Showing the 60 most looked-up of 2,597 medications checked with no known interaction — see the full Evening Primrose list.

See the full Evening Primrose interactions page
See every supplement checked against Naproxen, Sumatriptan, 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
Evening Primrose monograph › Uses, safety, and every drug interaction in one place Naproxen, Sumatriptan supplement interactions › Every supplement checked against Naproxen, Sumatriptan, ranked by severity 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 Evening Primrose and Naproxen, Sumatriptan Together: Common Questions

Can you take Evening Primrose with Naproxen, Sumatriptan?
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.
Why are there 2 interactions listed for Evening Primrose and Naproxen, Sumatriptan?
Naproxen, Sumatriptan belongs to more than one drug category, and Evening Primrose interacts with each of those categories a little differently. We list every one so nothing is missed — your overall risk is driven by the most serious of them.
How serious is the Evening Primrose and Naproxen, Sumatriptan 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

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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.