Drug & supplement interaction

Caffeine + Ethinyl estradiol, Levonogestrel

Ethinyl estradiol, Levonogestrel brand name: Lybrel.

Moderate Interaction
The bottom line Moderate

Ethinyl estradiol, Levonogestrel falls into 3 drug categories that Caffeine can interact with; the most serious is rated moderate. Theoretically, estrogens might increase the levels and adverse effects of caffeine.

Read the full interaction report
SeverityModerate
LikelihoodProbable
Interactions3
EvidenceB
What do Severity, Likelihood & Evidence mean?
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Interaction report

Caffeine and Ethinyl estradiol, Levonogestrel

These two interact in 3 distinct ways. Each one is explained separately below.

Why Are There 3 Interactions?

Caffeine interacts with whole categories of medication. Ethinyl estradiol, Levonogestrel falls into 3 of those categories, so it can interact with Caffeine in 3 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Moderate).

Moderate

ESTROGENS

1 of 3

Why this applies to Ethinyl estradiol, Levonogestrel

Ethinyl estradiol, Levonogestrel falls under ESTROGENS — the group Caffeine interacts with.

Theoretically, estrogens might increase the levels and adverse effects of 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 a flip from what most people expect: in this pairing, it's the birth control pill (Lybrel) that affects your caffeine, not the other way around. The estrogen part (ethinyl estradiol) slows down the liver enzyme that clears caffeine from your body. So the same cup of coffee or energy drink can linger longer and feel stronger than usual.

What that means in real life: you might notice more jitteriness, a racing or pounding heart, trouble falling asleep, or feeling wired and anxious. Nothing here makes your pill less effective, so don't worry about that. If caffeine seems to hit you harder since starting Lybrel, simply cutting back a bit usually helps. Chat with your pharmacist or doctor if you have questions.

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. Balogh, A., Klinger, G., Henschel, L., Borner, A., Vollanth, R., and Kuhnz, W. Influence of ethinylestradiol-containing combination oral contraceptives with gestodene or levonorgestrel on caffeine elimination. Eur.J.Clin.Pharmacol. 1995;48(2):161-166. PubMed
Minor

CYTOCHROME P450 1A2 (CYP1A2) INHIBITORS

2 of 3

Ethinyl estradiol, Levonogestrel also falls under CYTOCHROME P450 1A2 (CYP1A2) INHIBITORS.

Theoretically, concomitant use might increase the levels and adverse effects of 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 the key thing to understand: in this pairing, your birth control pill (the ethinyl estradiol and levonorgestrel in Lybrel) is acting on the caffeine, not the other way around. The estrogen part can gently slow down a liver enzyme called CYP1A2, which is the same enzyme that breaks down caffeine. When caffeine clears more slowly, it can hang around longer in your system.

In plain terms, your usual coffee or energy drink might hit a little harder or last longer, so you may notice more jitteriness, a racing heart, or trouble sleeping. That said, this is rated minor and is based only on lab data, not real patient studies. Most people won't notice much. If you feel wired, simply easing back on caffeine usually does the trick. Check with your pharmacist if you have questions.

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

CONTRACEPTIVE DRUGS

3 of 3

Ethinyl estradiol, Levonogestrel also falls under CONTRACEPTIVE DRUGS.

Theoretically, contraceptive drugs might increase the levels and adverse effects of caffeine.
Oral contraceptives decrease the rate of caffeine clearance by 40-65%.
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 small thing worth knowing if you take Lybrel (ethinyl estradiol with levonorgestrel) and you enjoy your coffee or tea. The interaction goes the opposite way from what most people expect: it's not that caffeine changes your birth control, it's that the birth control hormones slow down how fast your body clears caffeine, by roughly 40 to 65 percent. In plain terms, the same cup of coffee may hit you a little harder and stick around longer.

What that can feel like is more jitteriness, a racing or fluttery heartbeat, trouble sleeping, or feeling wired. This is rated minor and is mostly theoretical, so you don't need to quit caffeine. Just notice how you feel and ease back if you get those symptoms. Ask your pharmacist if you have questions.

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

Caffeine Also Interacts With Other Medications

Caffeine has 8 major, 482 moderate, 164 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.

Taking anything else?

Check Another of Your Medications Against Caffeine

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

From our Q&A

Questions About Caffeine or Ethinyl estradiol, Levonogestrel

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Caffeine or Ethinyl estradiol, Levonogestrel, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Ethinyl estradiol, Levonogestrel

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

We hold 6,775 real supplement products containing Caffeine, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Caffeine. Your product may carry other ingredients that interact with Ethinyl estradiol, Levonogestrel too, on top of Caffeine — 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 Caffeine 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 Caffeine
Top 5%

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

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

#125 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 Caffeine

What is Caffeine?

  • Mental alertness and reducing fatigue
  • Improving athletic performance
  • Headache and migraine relief
  • Boosting focus and concentration
  • Weight loss aid

Caffeine is a natural stimulant found in coffee, tea, and many other plants and products. In moderate amounts it can boost alertness and reduce tiredness for most healthy adults, but too much can cause jitteriness, a racing heart, and sleep problems. Pregnant women and people with heart conditions or anxiety should be especially careful and check with a doctor or pharmacist.

Read the full Caffeine monograph & all interactions
Keep checking

Other Drugs & Caffeine

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

8Major
482Moderate
164Minor
2,175No known interaction
Major

8 interactions

Moderate

482 interactions

Showing 60 of 482 moderate interactions — see all 482 on the Caffeine page.

Minor

164 interactions

Showing 60 of 164 minor interactions — see all 164 on the Caffeine page.

No interaction 2,175 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 Caffeine and Ethinyl estradiol, Levonogestrel Together: Common Questions

Can you take Caffeine 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 3 interactions listed for Caffeine and Ethinyl estradiol, Levonogestrel?
Ethinyl estradiol, Levonogestrel belongs to more than one drug category, and Caffeine 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 Caffeine 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

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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.