Drug & supplement interaction

Kudzu + Aspirin, Caffeine, Orphenadrine

Aspirin, Caffeine, Orphenadrine brand names: Norgesic Forte, Invagesic, Invagesic Forte, Orphengesic, Norgesic, and others.

Moderate Interaction
The bottom line Moderate

Aspirin, Caffeine, Orphenadrine falls into 2 drug categories that Kudzu can interact with; the most serious is rated moderate. Theoretically, kudzu may increase the risk of bleeding if used with antiplatelet or anticoagulant drugs.

Read the full interaction report
SeverityModerate
LikelihoodPossible
Interactions2
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Kudzu and Aspirin, Caffeine, Orphenadrine

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

Why Are There 2 Interactions?

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

Moderate

ANTICOAGULANT/ANTIPLATELET DRUGS

1 of 2

Why this applies to Aspirin, Caffeine, Orphenadrine

Aspirin, Caffeine, Orphenadrine falls under ANTICOAGULANT/ANTIPLATELET DRUGS — the group Kudzu interacts with.

Theoretically, kudzu may increase the risk of bleeding if used with antiplatelet or anticoagulant drugs.
Kudzu isoflavones are reported to have antiplatelet activity.
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

This combination product contains aspirin, which already thins the blood by blocking platelets from clumping together. Kudzu root contains plant compounds (isoflavones) that lab studies suggest may also have a mild blood-thinning effect. So in theory, taking kudzu alongside this medicine could add to that effect and slightly raise your chance of bruising, nosebleeds, or stomach upset and bleeding.

I want to be honest with you: this concern is theoretical, based on how these compounds behave, not on strong human studies. The caffeine and orphenadrine pieces aren't really involved here. Still, since aspirin can irritate the stomach on its own, it's worth a quick chat with your pharmacist or doctor before adding kudzu, especially if you bruise easily or have any bleeding history.

References
  1. Luo ZR, Zheng B. [Effect of Puerarin on platelet activating factors CD63 and CD62P, plasminogen activator inhibitor and C-reactive protein in patients with unstable angia pectoris]. Zhongguo Zhong Xi Yi Jie He Za Zhi 2001;21:31-3 .
  2. Yu Z, Zhang G, Zhao H. [Effects of Puerariae isoflavone on blood viscosity, thrombosis and platelet function]. Zhong Yao Cai 1997;20:468-9.
Moderate

CAFFEINE

2 of 2

Aspirin, Caffeine, Orphenadrine also falls under CAFFEINE.

Theoretically, taking kudzu with caffeine might increase levels of caffeine.
In healthy males injected with the kudzu constituent puerarin, caffeine clearance and metabolism is inhibited. This effect has been attributed to inhibition of cytochrome P450 1A2 (CYP1A2) enzyme, which is involved in caffeine metabolism. It is unclear if taking kudzu orally would have this same effect.
Severity Moderate Likelihood Probable Evidence D

Interaction 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..

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the piece that matters: this combo pill contains caffeine, and kudzu may slow down how your body clears caffeine. One of kudzu's compounds, puerarin, appears to block CYP1A2, the liver enzyme that breaks caffeine down. If caffeine lingers longer, you could feel more of its usual effects, like jitteriness, a racing or pounding heart, trouble sleeping, or feeling on edge.

I want to be honest about how solid this is, though. This is theoretical, and the clearest data came from injected puerarin, not kudzu taken by mouth, so we don't really know if oral kudzu does the same thing. If you take this medication regularly and want to try kudzu, just run it by your pharmacist or doctor first.

References
  1. Zheng, J., Chen, B., Jiang, B., Zeng, L., Tang, Z. R., Fan, L., and Zhou, H. H. The effects of puerarin on CYP2D6 and CYP1A2 activities in vivo. Arch Pharm Res 2010;33(2):243-246. 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

Kudzu Also Interacts With Other Medications

Kudzu has 511 moderate, 72 minor known drug interactions in our database — the Aspirin, Caffeine, Orphenadrine one above is among them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Kudzu

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

Everything else you take

See Every Supplement That Interacts With Aspirin, Caffeine, Orphenadrine

This page covers Kudzu only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Aspirin, Caffeine, Orphenadrine page lists 350 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 Ephedra (major).

By severity: 14 major · 289 moderate · 47 minor.

From our pharmacist’s overview on the Aspirin, Caffeine, Orphenadrine page

“Aspirin, caffeine, and orphenadrine (the Norgesic and Orphengesic brands) come with a supplement list that deserves real vigilance, with 14 of its 350 entries rated major. Over 200 of those ingredients can add to aspirin's effect on platelets and raise bleeding risk, another 44 stack stimulant effects on top of the caffeine, and grapef…”

Reviewed by 2 · Jul 18, 2026

Open the Aspirin, Caffeine, Orphenadrine interaction page

One more smart check

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

We hold 536 real supplement products containing Kudzu, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Kudzu. Your product may carry other ingredients that interact with Aspirin, Caffeine, Orphenadrine too, on top of Kudzu — 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 Kudzu and Aspirin, Caffeine, Orphenadrine 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 Kudzu
Top 25%

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

29 days ago today
Medication Aspirin, Caffeine, Orphenadrine
Top 5%

#80 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 Kudzu

What is Kudzu?

Kudzu
  • Alcohol cravings and reduction
  • Menopausal symptoms
  • Heart and blood vessel health
  • Hangover relief
  • Traditional Chinese medicine (Ge Gen)

Kudzu is a fast-growing vine whose root has long been used in traditional Chinese medicine and is now studied mostly for reducing alcohol intake. Early research is promising for cutting back on drinking, but evidence for most other uses is weak. Talk with your pharmacist or doctor before trying it, and avoid it during pregnancy and breastfeeding.

Read the full Kudzu monograph & all interactions
Keep checking

Other Drugs & Kudzu

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

0Major
511Moderate
72Minor
2,246No known interaction
Moderate

511 interactions

Showing 60 of 511 moderate interactions — see all 511 on the Kudzu page.

Minor

72 interactions

Showing 60 of 72 minor interactions — see all 72 on the Kudzu page.

No interaction 2,246 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 Kudzu and Aspirin, Caffeine, Orphenadrine Together: Common Questions

Can you take Kudzu with Aspirin, Caffeine, Orphenadrine?
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 2 interactions listed for Kudzu and Aspirin, Caffeine, Orphenadrine?
Aspirin, Caffeine, Orphenadrine belongs to more than one drug category, and Kudzu 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 Kudzu and Aspirin, Caffeine, Orphenadrine 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.