Drug & supplement interaction

Evodia + Ethinyl Estradiol, Norethindrone

Ethinyl Estradiol, Norethindrone brand names: Femhrt, Loestrin 21, Ovcon 35 21, Ovcon 50 28, Necon 0.5 35 21, and others.

Moderate Interaction
The bottom line Moderate

Ethinyl Estradiol, Norethindrone falls into 4 drug categories that Evodia can interact with; the most serious is rated moderate. Evodia might reduce the levels and clinical effects of CYP1A2 substrates through induction of CYP1A2.

Read the full interaction report
SeverityModerate
LikelihoodProbable
Interactions4
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Evodia and Ethinyl Estradiol, Norethindrone

These two interact in 4 distinct ways. Each one is explained separately below.

Why Are There 4 Interactions?

Evodia interacts with whole categories of medication. Ethinyl Estradiol, Norethindrone falls into 4 of those categories, so it can interact with Evodia in 4 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Moderate).

Moderate

CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES

1 of 4

Why this applies to Ethinyl Estradiol, Norethindrone

Ethinyl Estradiol, Norethindrone falls under CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES — the group Evodia interacts with.

Evodia might reduce the levels and clinical effects of CYP1A2 substrates through induction of CYP1A2.
Evodia extract and the evodia constituent rutaecarpine induce hepatic CYP1A2 enzyme activity. Evodia decreases levels of theophylline and caffeine, CYP1A2 substrates, by about 70% in animal models.
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 gist for your birth control pill: the estrogen part (ethinyl estradiol) is partly broken down by a liver enzyme called CYP1A2. Evodia appears to speed that enzyme up, so in theory it could clear the estrogen a little faster and lower its levels in your body. With a combination pill, anything that weakens hormone levels raises the worry of less reliable protection, breakthrough bleeding, or spotting.

That said, this is based only on test tube and animal research, not real people taking Evodia with the pill, so the actual effect in humans is unknown. I wouldn't panic, but I also wouldn't gamble with contraception. Please check with your pharmacist or doctor before combining them, and ask about backup protection if you do.

References
  1. Ueng YF, Tsai TH, Don MJ, et al. Alteration of the pharmacokinetics of theophylline by rutaecarpine, an alkaloid of the medicinal herb Evodia rutaecarpa, in rats. J Pharm Pharmacol 2005;57:227-32.
  2. Ueng YF, Jan WC, Lin LC, et al. The alkaloid rutaecarpine is a selective inhibitor of cytochrome P450 1A in mouse and human liver microsomes. Drug Metab Dispos 2002;30:349-53. PubMed
  3. Tsai TH, Chang CH, Lin LC. Effects of Evodia rutaecarpa and rutaecarpine on the pharmacokinetics of caffeine in rats. Planta Med 2005;71:640-5.
  4. Lee SK, Kim NH, Lee J, et al. Induction of cytochrome P450s by rutaecarpine and metabolism of rutaecarpine by cytochrome P450s. Planta Med 2004;70:753-7. PubMed
Moderate

CYTOCHROME P450 3A4 (CYP3A4) INHIBITORS

2 of 4

Ethinyl Estradiol, Norethindrone also falls under CYTOCHROME P450 3A4 (CYP3A4) INHIBITORS.

Theoretically, CYP3A4 inhibitors might increase the levels and clinical effects of evodia.
Animal research shows that concomitant administration of ketoconazole, a known CYP3A4 inhibitor, with the alkaloid constituents of evodia significantly increases the area under the curve (AUC), maximum concentration (Cmax), and half-life of these constituents.
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 thing to keep straight: this interaction works the other way around from what people often assume. Your birth control pill, the ethinyl estradiol with norethindrone combo, has mild blocking activity on a liver enzyme called CYP3A4. Evodia happens to be broken down by that same enzyme. So in theory, the pill could slow how fast your body clears evodia, letting the herb build up a bit more than expected.

I want to be honest about how soft this evidence is. It comes from test tube and animal work only, not real patients, so we're talking theoretical. Your pill itself shouldn't become weaker or stronger from this. Still, since evodia isn't well studied in people, I'd loop in your pharmacist or doctor before combining them.

References
  1. Zhang W, Guo J, Wang D, et al. Effect of CYP3A inducer/inhibitor on pharmacokinetics of five alkaloids in Evodiae Fructus. Chem Biol Interact 2020;327:109146. PubMed
Moderate

CYTOCHROME P450 1A2 (CYP1A2) INHIBITORS

3 of 4

Ethinyl Estradiol, Norethindrone also falls under CYTOCHROME P450 1A2 (CYP1A2) INHIBITORS.

Theoretically, drugs that inhibit CYP1A2 might increase the levels and clinical effects of evodia.
The evodia constituent rutaecarpine is metabolized by CYP1A2.
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 is the key thing to know about this particular pairing: the concern flows toward the Evodia, not your birth control pill. The estrogen part of your pill (ethinyl estradiol) can act as a mild blocker of a liver enzyme called CYP1A2. That same enzyme breaks down rutaecarpine, one of the active compounds in Evodia. So in theory, taking them together could let Evodia build up a bit higher and have stronger effects than expected.

I want to be honest about how soft this evidence is. It comes only from test tube and animal studies, not from people, so the real-world effect is likely small. Your contraceptive protection and side effects (like nausea or breast tenderness) shouldn't change. Still, it's worth running Evodia by your pharmacist or doctor before starting it.

References
  1. Lee SK, Kim NH, Lee J, et al. Induction of cytochrome P450s by rutaecarpine and metabolism of rutaecarpine by cytochrome P450s. Planta Med 2004;70:753-7. PubMed
Moderate

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES

4 of 4

Ethinyl Estradiol, Norethindrone also falls under CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES.

Theoretically, evodia might increase the levels and clinical effects of CYP3A4 substrates.
In vitro research shows that evodia extract inhibits hepatic CYP3A4. This effect has not been reported in humans.
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

Your birth control pill, which combines ethinyl estradiol with norethindrone, is processed in the liver by an enzyme called CYP3A4. Lab studies suggest evodia may slow that enzyme down. In theory, that could let more of the hormones build up in your body, which might mean more of the usual estrogen-related effects like nausea, breast tenderness, headaches, or bloating.

Here's the honest part: this has only been seen in test tube research, never in actual people, so it's a theoretical concern rather than a proven one. I wouldn't lose sleep over it, but since evodia hasn't been well studied in humans and you're relying on this pill, it's worth a quick chat with your pharmacist or doctor before combining them.

References
  1. Iwata H, Tezuka Y, Kadota S, et al. Mechanism-based inactivation of human liver microsomal CYP3A4 by rutaecarpine and limonin from Evodia fruit extract. Drug Metab Pharmacokinet 2005;20:34-45. 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

Evodia Also Interacts With Other Medications

Evodia has 949 moderate known drug interactions in our database — the Ethinyl Estradiol, Norethindrone 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 Evodia

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

Everything else you take

See Every Supplement That Interacts With Ethinyl Estradiol, Norethindrone

This page covers Evodia only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Ethinyl Estradiol, Norethindrone page lists 240 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 · 196 moderate · 38 minor.

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

“If you take a birth control pill or hormone therapy containing ethinyl estradiol and norethindrone (Loestrin, Femhrt, and others), a few supplements can genuinely undermine it, so read this page with care. Six of the 240 ingredients on file are rated major, and those six come first.”

Reviewed by 2 · Jul 18, 2026

Open the Ethinyl Estradiol, Norethindrone interaction page

One more smart check

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

We hold 182 real supplement products containing Evodia, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Evodia. Your product may carry other ingredients that interact with Ethinyl Estradiol, Norethindrone too, on top of Evodia — 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 Evodia and Ethinyl Estradiol, Norethindrone 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 Evodia
Top half

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

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

#450 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 Evodia

What is Evodia?

  • Digestive upset and nausea
  • Headaches
  • Menstrual cramps
  • Abdominal pain
  • Diarrhea

Evodia is a fruit used in traditional Chinese medicine, most often for digestive complaints, headaches, and menstrual pain. Human evidence for these uses is very limited, and it is mostly studied in laboratory and animal research. Talk with a pharmacist or doctor before using it, and avoid it during pregnancy and breastfeeding.

Read the full Evodia monograph & all interactions
Keep checking

Other Drugs & Evodia

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

0Major
949Moderate
0Minor
1,880No known interaction
Moderate

949 interactions

Showing 60 of 949 moderate interactions — see all 949 on the Evodia page.

No interaction 1,880 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 Evodia and Ethinyl Estradiol, Norethindrone Together: Common Questions

Can you take Evodia with Ethinyl Estradiol, Norethindrone?
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 4 interactions listed for Evodia and Ethinyl Estradiol, Norethindrone?
Ethinyl Estradiol, Norethindrone belongs to more than one drug category, and Evodia 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 Evodia and Ethinyl Estradiol, Norethindrone 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.