Drug & supplement interaction

Goji + Mefenamic Acid

Mefenamic Acid brand name: Ponstel.

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

Goji has a moderate interaction with Mefenamic Acid. Theoretically, goji berry might inhibit CYP2C9 and reduce metabolism of CYP2C9 substrates.

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

Goji and Mefenamic Acid

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

Moderate

CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES

Why this applies to Mefenamic Acid

Mefenamic Acid falls under CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES — the group Goji interacts with.

Theoretically, goji berry might inhibit CYP2C9 and reduce metabolism of CYP2C9 substrates.
In vitro research shows that goji berry tincture and juice inhibit CYP2C9 enzymes. Additionally, multiple case reports suggest that goji berry concentrated tea and juice inhibit the metabolism of warfarin, a CYP2C9 substrate. Concomitant use with goji may decrease metabolism and increase levels of CYP2C9 substrates.
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

Here's the short version: your body relies on a liver enzyme called CYP2C9 to clear mefenamic acid (Ponstel). Goji berry, especially in strong forms like concentrated juice, tincture, or brewed tea, may slow that enzyme down. Mefenamic acid is active as-is, not a prodrug, so if it clears more slowly it can build up a bit and its effects (including side effects) may be stronger than usual.

With an NSAID like this, that could mean more stomach upset, heartburn, nausea, or, over time, a higher risk of stomach irritation or bleeding. I'll be honest, the evidence here is thin and mostly theoretical or from lab studies, with the real concern seen in warfarin. A goji berry now and then as food is unlikely to matter. Still, if you're using concentrated goji supplements regularly, mention it to your pharmacist or doctor first.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Lam AY, Elmer GW, Mohutsky MA. Possible interaction between warfarin and Lycium Barbarum. Ann Pharmacother 2001;35:1199-201.
  2. Guzmán CE, Guzmán-Moreno CG, Assad-Morell JL, Edgar Francisco Carrizales-Sepúlveda EF. Flecainide toxicity associated with the use of goji berries: a case report. Eur Heart J Case Rep. 2021;5(6):ytab204. PubMed
  3. Liu R, Tam TW, Mao J, et al. In vitro activity of Lycium barbarum (Goji) against major human phase I metabolism enzymes. Complement Integr Med. 2016;13(3):257-265.

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

Goji Also Interacts With Other Medications

Goji has 2 major, 929 moderate, 68 minor known drug interactions in our database — the Mefenamic Acid one above is one of them. If you take anything else, check it against the full list below.

Major 2 Moderate 929 Minor 68 No known interaction 1,831 (incl. Mefenamic Acid)
Taking anything else?

Check Another of Your Medications Against Goji

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

Everything else you take

See Every Supplement That Interacts With Mefenamic Acid

This page covers Goji only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Mefenamic Acid page lists 118 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), Siberian Cocklebur (major) and Wine (major).

By severity: 5 major · 86 moderate · 27 minor.

From our pharmacist’s overview on the Mefenamic Acid page

“Mefenamic acid (Ponstel), an NSAID mostly used for menstrual cramps and short-term pain, has a supplement list that earns genuine caution, and the five major-rated entries are where to start. Beer and wine are two of them, because alcohol plus any NSAID raises the risk of stomach and intestinal bleeding.”

Reviewed by 2 · Jul 18, 2026

Open the Mefenamic Acid interaction page

One more smart check

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

We hold 1,738 real supplement products containing Goji, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Goji. Your product may carry other ingredients that interact with Mefenamic Acid too, on top of Goji — 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 Goji and Mefenamic Acid 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 Goji
Top 10%

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

29 days ago today
Medication Mefenamic Acid
Top 25%

#390 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 Goji

What is Goji?

Goji
  • General antioxidant support
  • Eye health
  • Immune support
  • Anti-aging and well-being
  • Blood sugar support

Goji berries are a nutritious fruit rich in antioxidants, vitamins, and plant polysaccharides, and they are safe for most people as a food. While they are popular for eye health, immune support, and general wellness, strong human evidence for most health claims is limited. Talk with your pharmacist or doctor before using concentrated goji supplements, especially if you take medications or are pregnant.

Read the full Goji monograph & all interactions
Medication

About Mefenamic Acid

What Is Mefenamic Acid Used For?

Brand name: Ponstel

Mefenamic acid capsules are approved to manage mild to moderate pain in adults and adolescents 14 years of age and older, but only for short-term use — no longer than 7 days.

They are also approved to treat primary dysmenorrhea (painful menstrual periods), started at the onset of bleeding and associated symptoms.

See full Mefenamic Acid drug information
Keep checking

Other Drugs & Goji

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

2Major
929Moderate
68Minor
1,830No known interaction
2 Major 929 Moderate 68 Minor 1,830 No interaction
Major

2 interactions

Moderate

929 interactions

Showing 60 of 929 moderate interactions — see all 929 on the Goji page.

Minor

68 interactions

Showing 60 of 68 minor interactions — see all 68 on the Goji page.

No interaction 1,830 drugs checked — show the list

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

Showing the 60 most looked-up of 1,830 medications checked with no known interaction — see the full Goji list.

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

Can you take Goji with Mefenamic Acid?
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 Goji and Mefenamic Acid 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 Mefenamic Acid and Goji?

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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.