Drug & supplement interaction

Green Tea + Rivaroxaban

Rivaroxaban brand name: Xarelto.

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

Rivaroxaban falls into 3 drug categories that Green Tea can interact with; the most serious is rated moderate. Green tea might increase the levels and adverse effects of P-glycoprotein (P-gp) substrates.

Read the full interaction report
SeverityModerate
LikelihoodPossible
Interactions3
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Green Tea and Rivaroxaban

These two interact in 3 distinct ways. Each one is explained separately below.

Why Are There 3 Interactions?

Green Tea interacts with whole categories of medication. Rivaroxaban falls into 3 of those categories, so it can interact with Green Tea in 3 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Moderate).

Moderate

P-GLYCOPROTEIN SUBSTRATES

1 of 3

Why this applies to Rivaroxaban

Rivaroxaban falls under P-GLYCOPROTEIN SUBSTRATES — the group Green Tea interacts with.

Green tea might increase the levels and adverse effects of P-glycoprotein (P-gp) substrates.
In vitro research and case reports suggest that green tea inhibits drug efflux by P-gp, potentially increasing serum levels of P-gp substrates. Case reports from the World Health Organization (WHO) adverse drug reaction database describe increased toxicity in patients taking green tea and certain P-gp 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 basics with Xarelto (rivaroxaban) and green tea. Your body uses a transporter called P-glycoprotein to help move rivaroxaban out of your system. Green tea, especially concentrated extracts, may slow that transporter down. In theory, that could let a bit more rivaroxaban build up in your blood, which for a blood thinner means a higher chance of bleeding problems like easy bruising, nosebleeds, bleeding gums, or blood in your urine or stool.

I want to be honest about how strong this is: it's based mostly on lab studies and a few scattered case reports, so it's a possible concern, not a proven one. A cup or two of green tea is unlikely to cause trouble. Higher-dose supplements are where I'd be more careful. If you're on Xarelto and want to take green tea pills, run it past your pharmacist or doctor first.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Pochet S, Lechon AS, Lescrainier C, et al. Herb-anticancer drug interactions in real life based on VigiBase, the WHO global database. Sci Rep 2022;12(1):14178. PubMed
Moderate

ANTICOAGULANT/ANTIPLATELET DRUGS

2 of 3

Rivaroxaban also falls under ANTICOAGULANT/ANTIPLATELET DRUGS.

Theoretically, green tea may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Conflicting reports exist regarding the effect of green tea on bleeding risk when used with anticoagulant or antiplatelet drugs; however, most evidence suggests that drinking green tea in moderate amounts is unlikely to cause a significant interaction. Green tea contains small amounts of vitamin K, approximately 7 mcg per cup. Some case reports have associated the antagonism of warfarin with the vitamin K content of green tea. However, these reports are rare, and very large doses of green tea (about 8-16 cups daily) appear to be needed to cause these effects. Furthermore, the catechins and caffeine in green tea are reported to have antiplatelet activity.
Severity Moderate 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 gist for Xarelto (rivaroxaban): it's a blood thinner that lowers your body's ability to form clots, so anything that nudges your bleeding risk up is worth a quick thought. Green tea is interesting because it has a small amount of vitamin K (roughly 7 mcg per cup), which in theory could slightly oppose a thinner, but it also contains catechins and caffeine that may nudge bleeding risk the other way. Honestly, the evidence here is weak and mostly theoretical, based on lab work and rare case reports.

For most folks, drinking a few cups of green tea a day alongside rivaroxaban is unlikely to cause a real problem. The concern is more with concentrated green tea extract supplements or very heavy intake. Watch for easy bruising, nosebleeds, or unusual bleeding, and check with your pharmacist or doctor before adding a green tea supplement.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Mitscher LA, Mitscher LA, Jung M, Shankel D, et al. Chemoprotection: a review of the potential therapeutic antioxidant properties of green tea (Camellia sinensis) and certain of its constituents. Med Res Rev 1997;17:327-65.
  2. Booth SL, Madabushi HT, Davidson KW, et al. Tea and coffee brews are not dietary sources of vitamin K-1 (phylloquinone). J Am Diet Assoc 1995;95:82-3. PubMed
  3. Lou FQ, Zhang MF, Zhang XG, et al. A study on tea-pigment in prevention of atherosclerosis. Chin Med J (Engl) 1989;102:579-83.
  4. Graham HN. Green tea composition, consumption, and polyphenol chemistry. Prev Med 1992;21:334-50. PubMed
  5. Taylor JR, Wilt VM. Probable antagonism of warfarin by green tea. Ann Pharmacother 1999;33:426-8. PubMed
  6. Heck AM, DeWitt BA, Lukes AL. Potential interactions between alternative therapies and warfarin. Am J Health Syst Pharm 2000;57:1221-7. DOI
  7. Ali M, Afzal M. A potent inhibitor of thrombin stimulated platelet thromboxane formation from unprocessed tea. Prostaglandins Leukot Med 1987;27:9-13. PubMed
  8. Ardlie NG, Glew G, Schultz BG, Schwartz CJ. Inhibition and reversal of platelet aggregation by methyl xanthines. Thromb Diath Haemorrh 1967;18:670-3. DOI
  9. Son DJ, Cho MR, Jin YR, et al. Antiplatelet effect of green tea catechins: a possible mechanism through arachidonic acid pathway. Prostaglandins Leukot Essent Fatty Acids 2004;71:25-31. PubMed
  10. Chan, H. T., So, L. T., Li, S. W., Siu, C. W., Lau, C. P., and Tse, H. F. Effect of herbal consumption on time in therapeutic range of warfarin therapy in patients with atrial fibrillation. J.Cardiovasc.Pharmacol. 2011;58(1):87-90. PubMed
  11. Nutescu EA, Shapiro NL, Ibrahim S, et al. Warfarin and its interactions with foods, herbs and other dietary supplements. Expert Opin Drug Saf. 2006;5(3):433-51. PubMed
Minor

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES

3 of 3

Rivaroxaban also falls under CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES.

Green tea is unlikely to produce clinically significant changes in the levels and clinical effects of CYP3A4 substrates.
In vitro and in vivo research suggests that green tea can inhibit intestinal CYP3A and induce hepatic CYP3A4 enzymes. However, this effect is unlikely to be clinically significant, as green tea does not appear to affect CYP3A4 activity in humans.
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 good news if you enjoy your daily cup: green tea and Xarelto (rivaroxaban) are very unlikely to cause a real problem together. Rivaroxaban is partly handled by a liver enzyme called CYP3A4, and lab studies show green tea can nudge that enzyme in both directions. But in actual people, green tea doesn't seem to meaningfully change how this drug works.

This is based on test-tube and animal research, not strong human evidence, so I wouldn't lose sleep over a few cups of tea. Where I'd be a little more cautious is with concentrated green tea extract pills, since those deliver much higher amounts than a beverage does. Since rivaroxaban is a blood thinner, anything that shifts its levels could in theory mean more bruising or bleeding, or a weaker clot-preventing effect. If you take supplements regularly, just give your pharmacist a heads-up.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Donovan JL, Chavin KD, Devane CL, et al. Green tea (Camellia sinensis) extract does not alter cytochrome P450 3A4 or 2D6 activity in healthy volunteers. Drug Metab Dispos 2004;32:906-8. PubMed
  2. Nishikawa, M., Ariyoshi, N., Kotani, A., Ishii, I., Nakamura, H., Nakasa, H., Ida, M., Nakamura, H., Kimura, N., Kimura, M., Hasegawa, A., Kusu, F., Ohmori, S., Nakazawa, K., and Kitada, M. Effects of continuous ingestion of green tea or grape seed extrac
  3. Chow, H. H., Hakim, I. A., Vining, D. R., Crowell, J. A., Cordova, C. A., Chew, W. M., Xu, M. J., Hsu, C. H., Ranger-Moore, J., and Alberts, D. S. Effects of repeated green tea catechin administration on human cytochrome P450 activity. Cancer Epidemiol.B PubMed
  4. Engdal, S. and Nilsen, O. G. In vitro inhibition of CYP3A4 by herbal remedies frequently used by cancer patients. Phytother.Res. 2009;23(7):906-912.
  5. Schönthal AH. Adverse effects of concentrated green tea extracts. Mol Nutr Food Res. 2011 Jun;55(6):874-85. 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

Green Tea Also Interacts With Other Medications

Green Tea has 13 major, 904 moderate, 375 minor known drug interactions in our database — the Rivaroxaban one above is among them. If you take anything else, check it against the full list below.

Major 13 Moderate 904 Minor 375 No known interaction 1,538 (incl. Rivaroxaban)
Taking anything else?

Check Another of Your Medications Against Green Tea

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

From our Q&A

Questions About Green Tea or Rivaroxaban

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

This page covers Green Tea only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Rivaroxaban page lists 285 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Danshen (major), Grapefruit (major), Piracetam (major) and St. John's Wort (major).

By severity: 5 major · 240 moderate · 40 minor.

From our pharmacist’s overview on the Rivaroxaban page

“Grapefruit is the interaction I would flag first for anyone taking rivaroxaban (Xarelto). It slows how the body clears this blood thinner, and higher levels mean more bleeding risk.”

Reviewed by 2 · Jul 18, 2026

Open the Rivaroxaban interaction page

One more smart check

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

We hold 9,084 real supplement products containing Green Tea, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Green Tea. Your product may carry other ingredients that interact with Rivaroxaban too, on top of Green Tea — 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 Green Tea and Rivaroxaban 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 Green Tea
Top 5%

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

29 days ago today
Medication Rivaroxaban
Top 10

#9 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 Green Tea

What is Green Tea?

Green Tea
  • Antioxidant support
  • Weight loss
  • Heart health
  • Mental alertness
  • Cancer risk reduction

Green tea is a popular beverage rich in antioxidants called catechins, and drinking it in normal amounts is considered safe for most people. Concentrated green tea extracts are a different story—they may help modestly with weight or heart health for some, but high doses have been linked to rare liver problems. Talk to your pharmacist or doctor before taking green tea supplements, especially if you have liver concerns or are pregnant.

Read the full Green Tea monograph & all interactions
Medication

About Rivaroxaban

What Is Rivaroxaban Used For?

Brand name: Xarelto

Rivaroxaban tablets are used to reduce the risk of stroke in adults with nonvalvular atrial fibrillation (an irregular heart rhythm), treat deep vein thrombosis (DVT, a blood clot in a vein) and pulmonary embolism (PE, a blood clot in the lungs), and lower the chances of these clots coming back. They also help prevent clots after hip or knee replacement surgery, protect hospitalized patients at risk for clots, and — in combination with aspirin — reduce the risk of major cardiovascular events in adults with coronary artery disease (CAD) or peripheral artery disease (PAD).

Rivaroxaban tablets are also approved for treating VTE (venous thromboembolism, blood clots in veins) and preventing recurrence in pediatric patients from birth to under 18 years, and for preventing clots in children aged 2 and older with congenital heart disease after the Fontan procedure. Rivaroxaban for oral suspension (available as Rivaroxaban Granule and Xarelto oral suspension) is specifically indicated for these two pediatric uses.

See full Rivaroxaban drug information
Keep checking

Other Drugs & Green Tea

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

13Major
904Moderate
375Minor
1,537No known interaction
13 Major 904 Moderate 375 Minor 1,537 No interaction
Major

13 interactions

Moderate

904 interactions

Showing 60 of 904 moderate interactions — see all 904 on the Green Tea page.

Minor

375 interactions

Showing 60 of 375 minor interactions — see all 375 on the Green Tea page.

No interaction 1,537 drugs checked — show the list

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

Showing the 60 most looked-up of 1,537 medications checked with no known interaction — see the full Green Tea list.

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

Can you take Green Tea with Rivaroxaban?
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 3 interactions listed for Green Tea and Rivaroxaban?
Rivaroxaban belongs to more than one drug category, and Green Tea 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 Green Tea and Rivaroxaban 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 Rivaroxaban and Green Tea?

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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.