Drug & supplement interaction

Phellodendron + Aspirin, Dipyridamole

Aspirin, Dipyridamole brand names: Aggrenox, Asasantin Retard.

Moderate Interaction
The bottom line Moderate

Phellodendron has a moderate interaction with Aspirin, Dipyridamole. Theoretically, phellodendron might increase the risk of bleeding when used with anticoagulant or antiplatelet drugs.

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

Phellodendron and Aspirin, Dipyridamole

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

Moderate

ANTICOAGULANT/ANTIPLATELET DRUGS

Why this applies to Aspirin, Dipyridamole

Aspirin, Dipyridamole falls under ANTICOAGULANT/ANTIPLATELET DRUGS — the group Phellodendron interacts with.

Theoretically, phellodendron might increase the risk of bleeding when used with anticoagulant or antiplatelet drugs.
Phellodendron contains berberine. In vitro and in vivo research suggest that berberine can inhibit platelet aggregation. Theoretically, phellodendron might also inhibit platelet aggregation.
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

Aggrenox is already a two-in-one blood thinner: the aspirin part and the dipyridamole part both make your platelets less sticky so clots are harder to form. That's exactly the job we want it to do after a stroke or TIA. Phellodendron contains berberine, which in lab and animal studies also seems to slow platelet clumping. Stack that on top of Aggrenox and, in theory, you could tip a little further toward easy bruising, nosebleeds, bleeding gums, or bleeding that's slow to stop.

I want to be honest about the strength here: this is theoretical, based on test-tube and animal work, not solid human studies. Still, since bleeding is the main risk with Aggrenox, it's worth a quick chat with your pharmacist or doctor before adding phellodendron.

References
  1. Wu, J. F. and Liu, T. P. [Effects of berberine on platelet aggregation and plasma levels of TXB2 and 6-keto-PGF1 alpha in rats with reversible middle cerebral artery occlusion]. Yao Xue.Xue.Bao. 1995;30(2):98-102.
  2. Tripathi YB and Shukla SD. Berberis artistata inhibits PAF induced aggregation of rabbit platelets. Phytotherapy Research 1996;10:628-630.

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

Phellodendron Also Interacts With Other Medications

Phellodendron has 1,159 moderate known drug interactions in our database — the Aspirin, Dipyridamole one above is one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Phellodendron

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

Everything else you take

See Every Supplement That Interacts With Aspirin, Dipyridamole

This page covers Phellodendron only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Aspirin, Dipyridamole page lists 243 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Adenosine (major), Asarabacca (major), Beer (major) and Danshen (major).

By severity: 8 major · 206 moderate · 29 minor.

From our pharmacist’s overview on the Aspirin, Dipyridamole page

“Aspirin with dipyridamole (Aggrenox) keeps platelets from clumping to prevent a second stroke, so it should be no surprise that the great bulk of this page is about bleeding. Most listed supplements can thin the blood further, and the risk reaches into ordinary life: beer and wine both carry major ratings because alcohol alongside aspi…”

Reviewed by 2 · Jul 18, 2026

Open the Aspirin, Dipyridamole interaction page

One more smart check

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

We hold 393 real supplement products containing Phellodendron, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Phellodendron. Your product may carry other ingredients that interact with Aspirin, Dipyridamole too, on top of Phellodendron — 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 Phellodendron and Aspirin, Dipyridamole 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 Phellodendron
Top 25%

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

29 days ago today
Medication Aspirin, Dipyridamole
Steady interest

#1,709 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 Phellodendron

What is Phellodendron?

Phellodendron
  • Digestive complaints and diarrhea
  • Inflammation and joint discomfort
  • Stress and weight management (in combination products)
  • Skin conditions (topical, traditional)
  • Antimicrobial support

Phellodendron is a traditional Chinese medicine bark (Huang Bai) that contains berberine and other plant compounds with antimicrobial and anti-inflammatory activity in lab studies. Human evidence for most uses is limited, and it is often sold in combination with other herbs, making its individual effects hard to judge. Talk with your pharmacist or doctor before using it, and avoid it during pregnancy and breastfeeding.

Read the full Phellodendron monograph & all interactions
Keep checking

Other Drugs & Phellodendron

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

0Major
1,159Moderate
0Minor
1,670No known interaction
Moderate

1,159 interactions

Showing 60 of 1,159 moderate interactions — see all 1,159 on the Phellodendron page.

No interaction 1,670 drugs checked — show the list
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

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Pharmacist Counseling Corner

Taking Phellodendron and Aspirin, Dipyridamole Together: Common Questions

Can you take Phellodendron with Aspirin, Dipyridamole?
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 Phellodendron and Aspirin, Dipyridamole 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.