Drug & supplement interaction

Kudzu + Ethiny Estradiol, Levonorgestrel

Ethiny Estradiol, Levonorgestrel brand names: Logynon, Microgynon 30 ED.

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

Kudzu has a moderate interaction with Ethiny Estradiol, Levonorgestrel. Theoretically, kudzu might alter the effects of estrogen therapy.

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

Kudzu and Ethiny Estradiol, Levonorgestrel

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

Moderate

ESTROGENS

Why this applies to Ethiny Estradiol, Levonorgestrel

Ethiny Estradiol, Levonorgestrel falls under ESTROGENS — the group Kudzu interacts with.

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

Your pill (Logynon or Microgynon) combines a man-made estrogen, ethinyl estradiol, with the progestin levonorgestrel. Kudzu root is packed with plant compounds called isoflavones that can act like weak estrogens in the body. On paper, adding these mild estrogen-like effects on top of your pill could nudge your hormone balance in either direction, possibly tweaking side effects like breast tenderness, mood changes, or breakthrough spotting.

Honestly, this is mostly theoretical. The concern comes from lab and limited human data, not strong proof that kudzu changes how well your birth control works. Still, since reliable contraception matters, I would not start kudzu without first checking with your pharmacist or doctor so they can weigh it for your situation.

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 Ethiny Estradiol, Levonorgestrel one above is one of them. If you take anything else, check it against the full list below.

Moderate 511 Minor 72 No known interaction 2,247 (incl. Ethiny Estradiol, Levonorgestrel)
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 Ethiny Estradiol, Levonorgestrel

This page covers Kudzu only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Ethiny Estradiol, Levonorgestrel page lists 214 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Grapefruit (major), St. John's Wort (major), Acacia Rigidula (moderate) and Adrafinil (moderate).

By severity: 3 major · 171 moderate · 40 minor.

From our pharmacist’s overview on the Ethiny Estradiol, Levonorgestrel page

“A supplement that lowers hormone levels in a birth control pill can mean an unplanned pregnancy, and St. John's wort can do exactly that to ethinyl estradiol and levonorgestrel (Logynon, Microgynon 30 ED) by speeding up how your liver clears the hormones.”

Reviewed by 2 · Jul 18, 2026

Open the Ethiny Estradiol, Levonorgestrel 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 Ethiny Estradiol, Levonorgestrel 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 Ethiny Estradiol, Levonorgestrel 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 Ethiny Estradiol, Levonorgestrel
Top 5%

#103 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 Ethiny Estradiol, Levonorgestrel, 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 Ethiny Estradiol, Levonorgestrel supplement interactions › Every supplement checked against Ethiny Estradiol, Levonorgestrel, 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 Ethiny Estradiol, Levonorgestrel Together: Common Questions

Can you take Kudzu with Ethiny Estradiol, Levonorgestrel?
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 Kudzu and Ethiny Estradiol, Levonorgestrel 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 Ethiny Estradiol, Levonorgestrel 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.