Drug & supplement interaction

Pau D'arco + Aspirin, Pentazocine

Aspirin, Pentazocine brand name: Talwin Compound.

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

Pau D'arco has a moderate interaction with Aspirin, Pentazocine. Theoretically, pau d'arco might increase the risk of bleeding when taken 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

Pau D'arco and Aspirin, Pentazocine

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

Moderate

ANTICOAGULANT/ANTIPLATELET DRUGS

Why this applies to Aspirin, Pentazocine

Aspirin, Pentazocine falls under ANTICOAGULANT/ANTIPLATELET DRUGS — the group Pau D'arco interacts with.

Theoretically, pau d'arco might increase the risk of bleeding when taken with anticoagulant or antiplatelet drugs.
In vitro research shows that pau d'arco reduces platelet aggregation and may interfere with vitamin K. One clinical study shows that taking the lapachol constituent of pau d'arco in doses above 1.5 grams daily increases the risk of bleeding. The effects of whole pau d'arco or pau d'arco extract in humans are unclear.
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

Talwin Compound combines aspirin with the pain reliever pentazocine. The piece that matters here is the aspirin, because aspirin already thins your blood a bit by keeping platelets from clumping together. Pau d'arco may do something similar in lab tests, and it might also nudge the way your body uses vitamin K, which helps blood clot.

Put those together and the worry is a little extra bleeding risk. In real life that could look like easier bruising, nosebleeds, bleeding gums, or a cut that takes longer to stop. Keep in mind this is theoretical, based mostly on lab work, and the concern grew clearest at high concentrated doses (over 1.5 grams of the lapachol constituent). Still, it is worth a quick chat with your pharmacist or doctor before combining them.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Gómez Castellanos JR, Prieto JM, Heinrich M. Red Lapacho (Tabebuia impetiginosa)--a global ethnopharmacological commodity? J Ethnopharmacol 2009;121:1-13. PubMed
  2. Son, D. J., Lim, Y., Park, Y. H., Chang, S. K., Yun, Y. P., Hong, J. T., Takeoka, G. R., Lee, K. G., Lee, S. E., Kim, M. R., Kim, J. H., and Park, B. S. Inhibitory effects of Tabebuia impetiginosa inner bark extract on platelet aggregation and vascular s
  3. Block JB, Serpick AA, Miller W, Wiernik PH. Early clinical studies with lapachol (NSC-11905). Cancer Chemother Rep 2. 1974;4(4):27-8.

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

Pau D'arco Also Interacts With Other Medications

Pau D'arco has 121 moderate known drug interactions in our database — the Aspirin, Pentazocine one above is one of them. If you take anything else, check it against the full list below.

Moderate 121 No known interaction 2,709 (incl. Aspirin, Pentazocine)
Taking anything else?

Check Another of Your Medications Against Pau D'arco

Covers the 2,830 medications we’ve checked against Pau D'arco. Pick one to open its full report.

Everything else you take

See Every Supplement That Interacts With Aspirin, Pentazocine

This page covers Pau D'arco only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Aspirin, Pentazocine page lists 336 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: 1,4-butanediol (major), Activated Charcoal (major), Asarabacca (major), Beer (major) and Danshen (major).

By severity: 11 major · 283 moderate · 42 minor.

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

“Talwin Compound pairs pentazocine, an opioid painkiller, with aspirin, and I read its supplement list with more concern than most. The great majority of entries do one of two things: raise the bleeding risk that aspirin already carries, or deepen the sedation pentazocine causes.”

Reviewed by 2 · Jul 18, 2026

Open the Aspirin, Pentazocine interaction page

One more smart check

Taking Pau D'arco as Part of a Dietary Supplement Product? Check It for Interactions

We hold 707 real supplement products containing Pau D'arco, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Pau D'arco. Your product may carry other ingredients that interact with Aspirin, Pentazocine too, on top of Pau D'arco — 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 Pau D'arco and Aspirin, Pentazocine 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 Pau D'arco
Top 25%

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

29 days ago today
Medication Aspirin, Pentazocine
Top 25%

#311 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 Pau D'arco

What is Pau D'arco?

Pau D'arco
  • Infections (bacterial, fungal, yeast)
  • Inflammation
  • Immune support
  • Digestive complaints
  • Skin conditions

Pau d'arco is a South American tree bark traditionally used for infections and inflammation, and it contains compounds like lapachol that show activity in lab studies. However, strong human evidence is lacking, and safety concerns exist at higher doses, so it should be used cautiously and discussed with a pharmacist or doctor first.

Read the full Pau D'arco monograph & all interactions
Keep checking

Other Drugs & Pau D'arco

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

0Major
121Moderate
0Minor
2,708No known interaction
121 Moderate 2,708 No interaction
Moderate

121 interactions

Showing 60 of 121 moderate interactions — see all 121 on the Pau D'arco page.

No interaction 2,708 drugs checked — show the list

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

Showing the 60 most looked-up of 2,708 medications checked with no known interaction — see the full Pau D'arco list.

See the full Pau D'arco interactions page
See every supplement checked against Aspirin, Pentazocine, 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
Pau D'arco monograph › Uses, safety, and every drug interaction in one place Aspirin, Pentazocine supplement interactions › Every supplement checked against Aspirin, Pentazocine, ranked by severity 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 Pau D'arco and Aspirin, Pentazocine Together: Common Questions

Can you take Pau D'arco with Aspirin, Pentazocine?
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 Pau D'arco and Aspirin, Pentazocine 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 Aspirin, Pentazocine and Pau D'arco?

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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.