Drug & supplement interaction

Cranberry + Diclofenac Potassium

Diclofenac Potassium brand names: Voltaren Rapide, Cataflam, Cataflam IR, Voltarol Rapid, Cambia.

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

Diclofenac Potassium falls into 2 drug categories that Cranberry can interact with; the most serious is rated minor. Theoretically, cranberry might increase the levels and adverse effects of CYP2C9 substrates.

Read the full interaction report
SeverityMinor
LikelihoodUnlikely
Interactions2
EvidenceB
What do Severity, Likelihood & Evidence mean?
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Interaction report

Cranberry and Diclofenac Potassium

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

Why Are There 2 Interactions?

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

Minor

CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES

1 of 2

Why this applies to Diclofenac Potassium

Diclofenac Potassium falls under CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES — the group Cranberry interacts with.

Theoretically, cranberry might increase the levels and adverse effects of CYP2C9 substrates. However, research is conflicting.
There is contradictory evidence about the effect of cranberry on CYP2C9 enzymes. In vitro evidence suggests that flavonoids in cranberry inhibit CYP2C9 enzymes. However, clinical research shows that cranberry juice does not significantly affect the levels, metabolism, or elimination of the CYP2C9 substrates flurbiprofen or diclofenac. Also, in patients stabilized on warfarin, drinking cranberry juice 250 mL daily for 7 days does not significantly increase the anticoagulant activity of warfarin, a CYP2C9 substrate. Additional pharmacokinetic research shows that cranberry juice does not increase peak plasma concentrations or area under the concentration-time curve of warfarin.
Severity Minor Likelihood Unlikely Evidence B

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 gist with cranberry and your diclofenac. Your liver uses an enzyme called CYP2C9 to break down diclofenac. In a test tube, some plant compounds in cranberry appear to slow that enzyme down, which in theory could let diclofenac build up a bit and nudge up side effects like stomach upset, heartburn, or a higher chance of stomach irritation. That's the worry on paper.

Here's the reassuring part: when researchers actually tested cranberry juice with diclofenac (and similar drugs), it didn't meaningfully change drug levels. So this interaction is rated minor and unlikely, and everyday cranberry intake shouldn't cause trouble. If you take diclofenac regularly or use concentrated cranberry supplements, just mention it to your pharmacist so they can keep an eye on things.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Anon. Possible interaction between warfarin and cranberry juice. Current Problems in Pharmacovigilance 2003;29:8. PubMed
  2. Greenblatt DJ, von Moltke LL, Perloff ES, et al. Interaction of flurbiprofen with cranberry juice, grape juice, tea, and fluconazole: in vitro and clinical studies. Clin Pharmacol Ther 2006;79:125-33. PubMed
  3. Hodek P, Trefil P, Stiborova M. Flavonoids-potent and versatile biologically active compounds interacting with cytochromes P450. Chem Biol Interact 2002;139:1-21.. PubMed
  4. Li Z, Seeram NP, Carpenter CL, et al. Cranberry does not affect prothrombin time in male subjects on warfarin. J Am Diet Assoc 2006;106:2057-61. PubMed
  5. Lilja JJ, Backman JT, Neuvonen PJ. Effects of daily ingestion of cranberry juice on the pharmacokinetics of warfarin, tizanidine, and midazolam - probes of CYP2C9, CYP1A2 and CYP3A4. Clin Pharmacol The 2007:81:833-9. PubMed
  6. Ushijima K, Tsuruoka S, Tsuda H, Hasegawa G, Obi Y, Kaneda T, Takahashi M, Maekawa T, Sasaki T, Koshimizu TA, Fujimura A. Cranberry juice suppressed the diclofenac metabolism by human liver microsomes, but not in healthy human subjects. Br J Clin Pharmaco PubMed
Minor

DICLOFENAC (Voltaren, others)

2 of 2
Theoretically, cranberry might modestly increase the levels and adverse effects of diclofenac.
In vitro evidence suggests that cranberry juice inhibits diclofenac metabolism by human liver microsomes. However, drinking cranberry juice does not seem to affect diclofenac metabolism in humans.
Severity Minor Likelihood Unlikely Evidence B

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 short version: your body clears diclofenac (including the potassium form found in Cataflam and Voltaren Rapide) using a liver enzyme. In a test tube, cranberry compounds slowed that enzyme down, which in theory could let diclofenac build up a bit and lead to more of its usual side effects, things like stomach upset, heartburn, or, with long use, irritation of the stomach lining.

But here's the reassuring part: when researchers actually had people drink cranberry juice, it did not meaningfully change how diclofenac was handled. So this is mostly a theoretical concern, rated minor and unlikely. Normal cranberry juice or a UTI supplement is very unlikely to cause a problem. If you take diclofenac regularly or notice new stomach discomfort, just mention it to your pharmacist or doctor.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Ushijima K, Tsuruoka S, Tsuda H, Hasegawa G, Obi Y, Kaneda T, Takahashi M, Maekawa T, Sasaki T, Koshimizu TA, Fujimura A. Cranberry juice suppressed the diclofenac metabolism by human liver microsomes, but not in healthy human subjects. Br J Clin Pharmaco 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

Cranberry Also Interacts With Other Medications

Cranberry has 643 moderate, 68 minor known drug interactions in our database — the Diclofenac Potassium one above is among them. If you take anything else, check it against the full list below.

Moderate 643 Minor 68 No known interaction 2,119 (incl. Diclofenac Potassium)
Taking anything else?

Check Another of Your Medications Against Cranberry

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

From our Q&A

Questions About Cranberry or Diclofenac Potassium

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

This page covers Cranberry only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Diclofenac Potassium page lists 306 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).

Open the Diclofenac Potassium interaction page

One more smart check

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

We hold 5,249 real supplement products containing Cranberry, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Cranberry. Your product may carry other ingredients that interact with Diclofenac Potassium too, on top of Cranberry — 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 Cranberry and Diclofenac Potassium 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 Cranberry
Top 5%

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

29 days ago today
Medication Diclofenac Potassium
Top 25%

#646 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 Cranberry

What is Cranberry?

Cranberry
  • Urinary tract infection prevention
  • Bladder health
  • Antioxidant support
  • Source of vitamin C

Cranberry is best known for helping to prevent repeated urinary tract infections (UTIs) in some people, and the evidence here is moderate but mixed. It is not a reliable treatment for an active UTI, which usually needs antibiotics. For most people cranberry products are well tolerated, but check with a pharmacist before relying on them, especially if you have frequent infections.

Read the full Cranberry monograph & all interactions
Medication

About Diclofenac

What Is Diclofenac Used For?

Brand names: Voltaren Rapide, Cataflam, Cataflam IR, Voltarol Rapid, Cambia

Diclofenac comes in many forms, and each one is approved for different uses. Which one you get depends on what you are treating.

  • Oral tablets: osteoarthritis, rheumatoid arthritis, and (delayed-release) ankylosing spondylitis, plus period pain and mild to moderate pain for the immediate-release potassium tablets.
  • Capsules: mild to moderate acute pain in adults.
  • Oral solution (powder for solution): acute treatment of migraine attacks in adults.
  • Topical gel and solution: osteoarthritis pain, mainly of the knees (and hands for the gel).
  • Skin patches (Flector, diclofenac epolamine): acute pain from minor strains, sprains and bruises.
See full Diclofenac drug information
Keep checking

Other Drugs & Cranberry

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

0Major
643Moderate
68Minor
2,118No known interaction
643 Moderate 68 Minor 2,118 No interaction
Moderate

643 interactions

Showing 60 of 643 moderate interactions — see all 643 on the Cranberry page.

Minor

68 interactions

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

No interaction 2,118 drugs checked — show the list

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

Showing the 60 most looked-up of 2,118 medications checked with no known interaction — see the full Cranberry list.

See the full Cranberry interactions page
See every supplement checked against Diclofenac Potassium, 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
Cranberry monograph › Uses, safety, and every drug interaction in one place Diclofenac Potassium supplement interactions › Every supplement checked against Diclofenac Potassium, 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 Cranberry and Diclofenac Potassium Together: Common Questions

Can you take Cranberry with Diclofenac Potassium?
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.
Why are there 2 interactions listed for Cranberry and Diclofenac Potassium?
Diclofenac Potassium belongs to more than one drug category, and Cranberry 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 Cranberry and Diclofenac Potassium 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 Diclofenac Potassium and Cranberry?

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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.