Drug & supplement interaction

Yerba Mate + 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
Medically reviewed by · Updated September 2026
The bottom line Moderate

Ethinyl Estradiol, Norethindrone falls into 4 drug categories that Yerba Mate can interact with; the most serious is rated moderate. Theoretically, estrogens might increase the levels and adverse effects of the caffeine in yerba mate.

Read the full interaction report
SeverityModerate
LikelihoodProbable
Interactions4
EvidenceB
What do Severity, Likelihood & Evidence mean?
Know someone taking this? Share
Facebook Post Reddit Email
On this page
Interaction report

Yerba Mate and Ethinyl Estradiol, Norethindrone

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

Why Are There 4 Interactions?

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

Moderate

ESTROGENS

1 of 4

Why this applies to Ethinyl Estradiol, Norethindrone

Ethinyl Estradiol, Norethindrone falls under ESTROGENS — the group Yerba Mate interacts with.

Theoretically, estrogens might increase the levels and adverse effects of the caffeine in yerba mate.
Yerba mate contains caffeine. Estrogen inhibits caffeine metabolism.
Severity Moderate Likelihood Probable Evidence B

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 thing to know about pairing yerba mate with a birth control pill like Loestrin or Ovcon (which combines ethinyl estradiol and norethindrone). It's not really the pill that gets affected here, it's the caffeine in the mate. The estrogen in your pill slows down how fast your body clears caffeine, so that cup of mate can hang around longer and hit harder than usual.

In plain terms, you may feel more of the caffeine: jitteriness, a racing heart, trouble sleeping, or an upset stomach. Your pill keeps working fine for birth control. If you notice you're more wired than expected, try cutting back on mate or other caffeine, and check in with your pharmacist if it bothers you.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Pollock BG, Wylie M, Stack JA, et al. Inhibition of caffeine metabolism by estrogen replacement therapy in postmenopausal women. J Clin Pharmacol 1999;39:936-40. PubMed
Minor

CYTOCHROME P450 1A2 (CYP1A2) INHIBITORS

2 of 4

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

Theoretically, concomitant use of CYP1A2 inhibitors and yerba mate might increase levels and adverse effects of the caffeine in yerba mate.
Yerba mate contains caffeine. Caffeine is metabolized by CYP1A2. Theoretically, drugs that inhibit CYP1A2 may decrease the rate of caffeine clearance and increase caffeine levels.
Severity Minor 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 something many people don't realize about birth control pills like Loestrin or Ovcon: the estrogen part (ethinyl estradiol) can gently slow down the same liver enzyme, CYP1A2, that your body uses to clear caffeine. Yerba mate is loaded with caffeine, so pairing the two could mean the caffeine hangs around a bit longer than usual.

In real life, that might show up as feeling more jittery, a racing or pounding heart, trouble sleeping, or an upset stomach. Importantly, this is theoretical, based on how these compounds behave, not on strong patient studies, and it's rated as minor. A cup or two of mate is unlikely to cause trouble. If you drink a lot or notice the buzz feels stronger than before, just chat with your pharmacist or doctor.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Hagg S, Spigset O, Mjorndal T, Dahlqvist R. Effect of caffeine on clozapine pharmacokinetics in healthy volunteers. Br J Clin Pharmacol 2000;49:59-63. PubMed
  2. Carrillo JA, Benitez J. Clinically significant pharmacokinetic interactions between dietary caffeine and medications. Clin Pharmacokinet 2000;39:127-53. PubMed
Minor

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES

3 of 4

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

Theoretically, yerba mate might increase the levels and clinical effects of CYP3A4 substrates.
In vitro research shows that yerba mate extract inhibits CYP3A4 enzymes. Theoretically, taking yerba mate may increase levels and adverse effects of CYP3A4 substrates.
Severity Minor 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 combines two active hormones, ethinyl estradiol and norethindrone, and your body partly clears the estrogen part using a liver enzyme called CYP3A4. Lab studies (in a test tube, not in people) hint that yerba mate may slow this enzyme down a little. If that happened in real life, the estrogen could linger a bit longer, which in theory might mean slightly more of the usual side effects like nausea, breast tenderness, bloating, headaches, or spotting.

Honestly, this is a very weak, theoretical concern. The evidence comes only from cell studies, and normal mate drinking is unlikely to throw off your pill. Keep enjoying it in moderation, but mention your mate habit to your pharmacist or doctor if you have any worries.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Feltrin C, Farias IV, Sandjo LP, Reginatto FH, Simões CMO. Effects of Standardized Medicinal Plant Extracts on Drug Metabolism Mediated by CYP3A4 and CYP2D6 Enzymes. Chem Res Toxicol 2020;33(9):2408-2419. PubMed
Minor

CONTRACEPTIVE DRUGS

4 of 4

Ethinyl Estradiol, Norethindrone also falls under CONTRACEPTIVE DRUGS.

Theoretically, contraceptive drugs might increase the levels and adverse effects of the caffeine contained in yerba mate.
Yerba mate contains caffeine. Contraceptive drugs decrease the rate of caffeine clearance by 40% to 65%.
Severity Minor 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 a little twist on how this one works: it isn't your birth control pill that gets affected, it's the caffeine in the yerba mate. The estrogen in your pill (ethinyl estradiol) slows down how quickly your body clears caffeine, by roughly 40% to 65%. So that mate can linger longer and hit harder than usual.

In real life, that might mean feeling more jittery, a racing or pounding heart, trouble sleeping, or an upset stomach, especially if you drink several cups. This is considered a minor interaction, and a small amount of mate is unlikely to cause trouble. If you notice you're more wired than expected, just cut back a bit or switch to a lower-caffeine option, and check with your pharmacist if you're unsure.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Pollock BG, Wylie M, Stack JA, et al. Inhibition of caffeine metabolism by estrogen replacement therapy in postmenopausal women. J Clin Pharmacol 1999;39:936-40. PubMed
  2. Abernethy DR, Todd EL. Impairment of caffeine clearance by chronic use of low-dose oestrogen-containing oral contraceptives. Eur J Clin Pharmacol 1985;28:425-8. 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

Yerba Mate Also Interacts With Other Medications

Yerba Mate has 8 major, 504 moderate, 573 minor 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.

Major 8 Moderate 504 Minor 573 No known interaction 1,745 (incl. Ethinyl Estradiol, Norethindrone)
Taking anything else?

Check Another of Your Medications Against Yerba Mate

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

Everything else you take

See Every Supplement That Interacts With Ethinyl Estradiol, Norethindrone

This page covers Yerba Mate 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 Yerba Mate as Part of a Dietary Supplement Product? Check It for Interactions

We hold 68 real supplement products containing Yerba Mate, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Yerba Mate. Your product may carry other ingredients that interact with Ethinyl Estradiol, Norethindrone too, on top of Yerba Mate — 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 Yerba Mate 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 Yerba Mate
Top half

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

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

#447 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 Yerba Mate

What is Yerba Mate?

Yerba Mate
  • Energy and alertness
  • Weight loss
  • Mental focus
  • Digestive support
  • Antioxidant support

Yerba mate is a caffeine-containing herbal beverage from South America that is widely enjoyed for its stimulating, coffee-like effects. While it is rich in antioxidants and is being studied for weight, blood sugar, and cholesterol, strong human evidence for most health claims is limited. Drinking very hot mate over many years has been linked to higher risk of certain cancers, so enjoy it warm and in moderation.

Read the full Yerba Mate monograph & all interactions
Keep checking

Other Drugs & Yerba Mate

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

8Major
504Moderate
573Minor
1,744No known interaction
8 Major 504 Moderate 573 Minor 1,744 No interaction
Major

8 interactions

Moderate

504 interactions

Showing 60 of 504 moderate interactions — see all 504 on the Yerba Mate page.

Minor

573 interactions

Showing 60 of 573 minor interactions — see all 573 on the Yerba Mate page.

No interaction 1,744 drugs checked — show the list

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

Showing the 60 most looked-up of 1,744 medications checked with no known interaction — see the full Yerba Mate list.

See the full Yerba Mate interactions page
See every supplement checked against Ethinyl Estradiol, Norethindrone, 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
Yerba Mate monograph › Uses, safety, and every drug interaction in one place Ethinyl Estradiol, Norethindrone supplement interactions › Every supplement checked against Ethinyl Estradiol, Norethindrone, 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 Yerba Mate and Ethinyl Estradiol, Norethindrone Together: Common Questions

Can you take Yerba Mate 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 Yerba Mate and Ethinyl Estradiol, Norethindrone?
Ethinyl Estradiol, Norethindrone belongs to more than one drug category, and Yerba Mate 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 Yerba Mate 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

Still Have a Question About Ethinyl Estradiol, Norethindrone and Yerba Mate?

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.