Drug & supplement interaction

Kudzu + Etonogestrel, Ethinyl Estradiol

Etonogestrel, Ethinyl Estradiol brand name: NuvaRing.

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

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

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

Kudzu and Etonogestrel, Ethinyl Estradiol

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

Moderate

ESTROGENS

Why this applies to Etonogestrel, Ethinyl Estradiol

Etonogestrel, Ethinyl Estradiol 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 NuvaRing slowly releases two hormones, a progestin (etonogestrel) and an estrogen (ethinyl estradiol), to prevent pregnancy and steady your cycle. Kudzu root contains plant compounds called isoflavones that behave like weak estrogens. In theory, adding that mild estrogen-like activity on top of your ring could nudge your hormonal balance, possibly bumping up estrogen-type effects like breast tenderness, bloating, nausea, or breakthrough spotting. In some cases the opposite, a slight blunting, is possible too.

I want to be honest about the evidence here. This is mostly theoretical and based on weak research, so it's far from certain. I'm not telling you to avoid kudzu or change your ring. Just give your pharmacist or doctor a quick heads-up before starting it so they can keep an eye on things.

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 Etonogestrel, Ethinyl Estradiol 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. Etonogestrel, Ethinyl Estradiol)
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 Etonogestrel, Ethinyl Estradiol

This page covers Kudzu only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Etonogestrel, Ethinyl Estradiol page lists 203 supplements it has a documented interaction with, worst first, each one explained.

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

By severity: 2 major · 168 moderate · 33 minor.

From our pharmacist’s overview on the Etonogestrel, Ethinyl Estradiol page

“St. John's wort belongs at the top of any conversation about NuvaRing (etonogestrel and ethinyl estradiol) and supplements.”

Reviewed by 2 · Jul 18, 2026

Open the Etonogestrel, Ethinyl Estradiol 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 Etonogestrel, Ethinyl Estradiol 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 Etonogestrel, Ethinyl Estradiol 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%

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

29 days ago today
Medication Etonogestrel, Ethinyl Estradiol
Top 25%

#680 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 Etonogestrel, Ethinyl Estradiol, 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 Etonogestrel, Ethinyl Estradiol supplement interactions › Every supplement checked against Etonogestrel, Ethinyl Estradiol, 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 Etonogestrel, Ethinyl Estradiol Together: Common Questions

Can you take Kudzu with Etonogestrel, Ethinyl Estradiol?
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 Etonogestrel, Ethinyl Estradiol 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 Etonogestrel, Ethinyl Estradiol and Kudzu?

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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.