Drug & supplement interaction

Pu-erh Tea + Warfarin Sodium

Warfarin Sodium brand names: Coumadin, Panwarfin, Sofarin.

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

Pu-erh Tea has a moderate interaction with Warfarin Sodium. Theoretically, pu-erh tea may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.

Read the full interaction report
SeverityModerate
LikelihoodPossible
EvidenceD
What do Severity, Likelihood & Evidence mean?
Know someone taking this? Share
Facebook Post Reddit Email
On this page
Interaction report

Pu-erh Tea and Warfarin Sodium

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

Moderate

ANTICOAGULANT/ANTIPLATELET DRUGS

Why this applies to Warfarin Sodium

Warfarin Sodium falls under ANTICOAGULANT/ANTIPLATELET DRUGS — the group Pu-erh Tea interacts with.

Theoretically, pu-erh tea may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Pu-erh tea contains caffeine. Caffeine is reported to have antiplatelet activity. Theoretically, the caffeine in pu-erh tea might increase the risk of bleeding when used concomitantly with antiplatelet drugs. However, this interaction has not been reported in humans.
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 quick picture with warfarin and pu-erh tea. The concern is that the caffeine in pu-erh may have a mild blood-thinning (antiplatelet) effect of its own. Stack that on top of warfarin, which already lowers your blood's ability to clot, and in theory you could nudge your bleeding risk up a little. Realistic signs would be things like easy bruising, nosebleeds, bleeding gums, or blood in your urine or stool.

The good news: this is a theoretical worry based only on lab work, and it has never actually been reported in people drinking tea. Still, warfarin is a finicky drug where small shifts matter, so don't make big changes to your tea habit without a heads-up. Keep your intake steady and let your pharmacist or doctor know.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Ali M, Afzal M. A potent inhibitor of thrombin stimulated platelet thromboxane formation from unprocessed tea. Prostaglandins Leukot Med 1987;27:9-13. PubMed
  2. 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
  3. Steptoe, A., Gibson, E. L., Vuononvirta, R., Hamer, M., Wardle, J., Rycroft, J. A., Martin, J. F., and Erusalimsky, J. D. The effects of chronic tea intake on platelet activation and inflammation: a double-blind placebo controlled trial. Atherosclerosis 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

Pu-erh Tea Also Interacts With Other Medications

Pu-erh Tea has 9 major, 447 moderate, 210 minor known drug interactions in our database — the Warfarin Sodium one above is one of them. If you take anything else, check it against the full list below.

Major 9 Moderate 447 Minor 210 No known interaction 2,164 (incl. Warfarin Sodium)
Taking anything else?

Check Another of Your Medications Against Pu-erh Tea

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

From our Q&A

Questions About Pu-erh Tea or Warfarin 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 Pu-erh Tea or Warfarin 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 Warfarin Sodium

This page covers Pu-erh Tea only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Warfarin Sodium page lists 361 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Alfalfa (major), American Ginseng (major), Beer (major) and Cannabis (major).

Open the Warfarin Sodium interaction page

How much people look this up

Where Pu-erh Tea and Warfarin 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 Pu-erh Tea
Steady interest

#1,340 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Warfarin Sodium
Top 1%

#19 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 Pu-erh Tea

What is Pu-erh Tea?

  • Weight management
  • Cholesterol and heart health
  • Digestion after meals
  • Mental alertness
  • General antioxidant support

Pu-erh tea is a fermented, aged form of tea made from the same plant as green and black tea. It is enjoyed worldwide as a beverage and is sometimes promoted for weight loss, cholesterol, and digestion, but human evidence for these uses is limited. As a normal drink it is generally well tolerated, though it does contain caffeine.

Read the full Pu-erh Tea monograph & all interactions
Medication

About Warfarin

What Is Warfarin Used For?

Brand names: Coumadin, Panwarfin, Sofarin

Warfarin sodium tablets and Jantoven tablets are both used to prevent and treat venous thrombosis (blood clots in the veins) and pulmonary embolism (a clot in the lungs). They are also used to prevent clot-related complications in people with atrial fibrillation (an irregular heart rhythm) or who have had a heart valve replaced.

In people who have had a heart attack, warfarin is used to reduce the risk of death, another heart attack, stroke, or other clotting events. It does not dissolve an existing clot, but it helps prevent the clot from growing and stops new dangerous clots from forming.

See full Warfarin drug information
Keep checking

Other Drugs & Pu-erh Tea

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

9Major
447Moderate
210Minor
2,163No known interaction
9 Major 447 Moderate 210 Minor 2,163 No interaction
Major

9 interactions

Moderate

447 interactions

Showing 60 of 447 moderate interactions — see all 447 on the Pu-erh Tea page.

Minor

210 interactions

Showing 60 of 210 minor interactions — see all 210 on the Pu-erh Tea page.

No interaction 2,163 drugs checked — show the list

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

Showing the 60 most looked-up of 2,163 medications checked with no known interaction — see the full Pu-erh Tea list.

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

Can you take Pu-erh Tea with Warfarin 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 Pu-erh Tea and Warfarin 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 Warfarin Sodium and Pu-erh Tea?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

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.