Drug & supplement interaction

Kudzu + Ethinyl estradiol, Levonogestrel

Ethinyl estradiol, Levonogestrel brand name: Lybrel.

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

Ethinyl estradiol, Levonogestrel falls into 2 drug categories that Kudzu can interact with; the most serious is rated moderate. Theoretically, concomitant use might have additive hepatotoxic effects.

Read the full interaction report
SeverityModerate
LikelihoodPossible
Interactions2
EvidenceD
What do Severity, Likelihood & Evidence mean?
Know someone taking this? Share
Facebook Post Reddit Email
On this page
Interaction report

Kudzu and Ethinyl estradiol, Levonogestrel

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. Ethinyl estradiol, Levonogestrel 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

HEPATOTOXIC DRUGS

1 of 2

Why this applies to Ethinyl estradiol, Levonogestrel

Ethinyl estradiol, Levonogestrel falls under HEPATOTOXIC DRUGS — the group Kudzu interacts with.

Theoretically, concomitant use might have additive hepatotoxic effects.
There is some concern that kudzu can adversely affect the liver.
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 gist with kudzu and your birth control pill (Lybrel, which combines ethinyl estradiol and levonorgestrel). Both of these are processed by your liver, and there's a theory that kudzu could be hard on the liver too. The worry is simply that stacking two things the liver has to handle might add up. To be clear, this is a theoretical concern based on how things work on paper, not strong proof from real patients, so I don't want you to panic.

If you do take kudzu alongside your pill, just keep an eye out for liver warning signs like unusual tiredness, yellowing of the skin or eyes, dark urine, or pain in the upper right belly. Please run this by your pharmacist or doctor before combining them so they can weigh it for your situation.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Kim HJ, Kim H, Ahn JH, Suk JH. Liver injury induced by herbal extracts containing mistletoe and kudzu. J Altern Complement Med 2015;21(3):180-5. PubMed
  2. Santosh N, Mohan K, Royana S, Yamini TB. Hepatotoxicity of tubers of Indian Kudzu (Pueraria tuberosa) in rats. Food Chem Toxicol. 2010 Apr;48(4):1066-71. PubMed
  3. Teschke R, Zhang L, Long H, Schwarzenboeck A, Schmidt-Taenzer W, Genthner A, Wolff A, Frenzel C, Schulze J, Eickhoff A. Traditional Chinese Medicine and herbal hepatotoxicity: a tabular compilation of reported cases. Ann Hepatol. 2015 Jan-Feb;14(1):7-19. DOI
  4. Wang D, Qiu L, Wu X, Wei H, Xu F. Evaluation of kudzu root extract-induced hepatotoxicity. J Ethnopharmacol. 2015 Dec 24;176:321-6. PubMed
Moderate

ESTROGENS

2 of 2

Ethinyl estradiol, Levonogestrel also falls under ESTROGENS.

Theoretically, kudzu might alter the effects of estrogen therapy.
Some research suggests that kudzu has estrogenic effects. This may enhance or inhibit the effects of estrogen therapy.
Severity Moderate Likelihood Possible Evidence B

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 thing about kudzu and a pill like Lybrel (which combines ethinyl estradiol and levonorgestrel): kudzu root is loaded with plant compounds called isoflavones that can act like weak estrogens in your body. Because your birth control already delivers a carefully measured estrogen dose, adding something with its own mild estrogen-like activity could theoretically nudge those effects in either direction, either adding to them or muddying them.

I want to be honest that this is mostly theoretical and the research is on the weaker side, so I'm not ringing alarm bells. Still, since this pill works best at steady, predictable levels, it's worth a quick chat with your pharmacist or doctor before starting kudzu rather than guessing.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Woo J, Lau E, Ho SC, et al. Comparison of Pueraria lobata with hormone replacement therapy in treating the adverse health consequences of menopause. Menopause 2003;10:352-61. PubMed
  2. Zheng, G., Zhang, X., Zheng, J., Meng, Q., and Zheng, D. [Estrogen-like effects of puerarin and total isoflavones from Pueraria lobata]. Zhong.Yao Cai. 2002;25(8):566-568.
  3. Qi, B. L. and Qi, B. M. [Effect of the purariae-isofiavones on estrogen level in normal and ovariectomized rats]. Zhongguo Zhong.Yao Za Zhi. 2002;27(11):850-852.

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 Ethinyl estradiol, Levonogestrel one above is among them. If you take anything else, check it against the full list below.

Moderate 511 Minor 72 No known interaction 2,247 (incl. Ethinyl estradiol, Levonogestrel)
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 Ethinyl estradiol, Levonogestrel

This page covers Kudzu only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Ethinyl estradiol, Levonogestrel page lists 239 supplements it has a documented interaction with, worst first, each one explained.

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

By severity: 6 major · 195 moderate · 38 minor.

From our pharmacist’s overview on the Ethinyl estradiol, Levonogestrel page

“A daily birth control pill like Lybrel (ethinyl estradiol with levonorgestrel) only works when enough hormone stays in the bloodstream, and that is exactly what several supplements on this page can undermine. This list deserves genuine care, starting with the six major-rated entries.”

Reviewed by 2 · Jul 18, 2026

Open the Ethinyl estradiol, Levonogestrel 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 Ethinyl estradiol, Levonogestrel 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 Ethinyl estradiol, Levonogestrel 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%

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

29 days ago today
Medication Ethinyl estradiol, Levonogestrel
Top 5%

#117 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
511 Moderate 72 Minor 2,246 No 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

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

Showing the 60 most looked-up of 2,246 medications checked with no known interaction — see the full Kudzu list.

See the full Kudzu interactions page
See every supplement checked against Ethinyl estradiol, Levonogestrel, 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
Kudzu monograph › Uses, safety, and every drug interaction in one place Ethinyl estradiol, Levonogestrel supplement interactions › Every supplement checked against Ethinyl estradiol, Levonogestrel, 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 Kudzu and Ethinyl estradiol, Levonogestrel Together: Common Questions

Can you take Kudzu with Ethinyl estradiol, Levonogestrel?
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 Ethinyl estradiol, Levonogestrel?
Ethinyl estradiol, Levonogestrel 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 Ethinyl estradiol, Levonogestrel 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 Ethinyl estradiol, Levonogestrel and Kudzu?

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.