Drug & supplement interaction

Hops + Estradiol, Norethindrone Acetate

Estradiol, Norethindrone Acetate brand name: Activella.

Moderate Interaction
The bottom line Moderate

Estradiol, Norethindrone Acetate falls into 3 drug categories that Hops can interact with; the most serious is rated moderate. Theoretically, concomitant use of large amounts of hops might interfere with hormone replacement therapy due to competition for estrogen receptors.

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

Hops and Estradiol, Norethindrone Acetate

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

Why Are There 3 Interactions?

Hops interacts with whole categories of medication. Estradiol, Norethindrone Acetate falls into 3 of those categories, so it can interact with Hops 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 Estradiol, Norethindrone Acetate

Estradiol, Norethindrone Acetate falls under ESTROGENS — the group Hops interacts with.

Theoretically, concomitant use of large amounts of hops might interfere with hormone replacement therapy due to competition for estrogen receptors.
In vitro research suggests that certain hops constituents can competitively bind to estrogen receptors. However, most hops extracts contain very small amounts 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

Activella combines estradiol with a progestin to ease menopause symptoms like hot flashes and night sweats. Here's the thing about hops: one of its compounds, called 8-prenylnaringenin, is a surprisingly strong plant estrogen, and lab studies show certain hops pieces can compete with estrogen at the same receptors your medicine works on. In theory, large amounts could slightly nudge how your estradiol behaves.

I want to be honest, though. This concern is based only on test-tube research, and most hops products contain very tiny amounts of that compound. A cup of hops tea or short-term sleep use is unlikely to throw off your therapy. If you're using concentrated, high-dose hops supplements regularly, just mention it to your pharmacist or doctor first.

References
  1. Zava DT, Dollbaum CM, Blen M. Estrogen and progestin bioactivity of foods, herbs, and spices. Proc Soc Exp Biol Med 1998;217:369-78. PubMed
  2. Milligan SR, Kalita JC, Heyerick A, et al. Identification of a potent phytoestrogen in hops (Humulus lupulus L.) and beer. J Clin Endocrinol Metab 1999;84:2249-52.. PubMed
  3. Milligan SR, Kalita JC, Pocock V, et al. The endocrine activities of 8-prenylnaringenin and related hop (Humulus lupulus L.) flavonoids. J Clin Endocrinol Metab 2000;85:4912-5.. DOI
  4. Assessment report on Humulus lupulus L., flos. European Medicines Agency, 2014. Available at: https://www.ema.europa.eu/en/documents/herbal-report/final-assessment-report-humulus-lupulus-l-flos_en.pdf. Accessed September 29, 2021.
Minor

CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES

2 of 3

Estradiol, Norethindrone Acetate also falls under CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES.

Hops extract does not seem to affect the metabolism of CYP1A2 substrates.
In vitro research suggests that flavonoid constituents of hops inhibit CYP1A2 enzyme activity. However, a pharmacokinetic study in healthy postmenopausal patients shows that taking a standardized extract of spent hops containing prenylated phenols, as 59.5 mg twice daily for 2 weeks, does not affect levels of caffeine, a CYP1A2 probe substrate.
Severity Minor Likelihood Unlikely Evidence D

Interaction has been demonstrated in animal or in lab research but has been shown not to occur in humans..

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

If you're taking Activella (a combination of estradiol and norethindrone for menopause symptoms), here's the good news about adding hops. On paper, hops contain flavonoids that can mildly slow a liver enzyme called CYP1A2, which plays a small part in handling estrogen. That raised a theoretical question about whether hops could nudge your hormone levels up.

But the real-world evidence is reassuring. A study in postmenopausal women found that a standardized hops extract did not meaningfully change how the body processes substances cleared by that enzyme. So we don't expect hops to boost side effects like breast tenderness, bloating, or spotting in any noticeable way. This is a minor, unlikely concern, but since hops itself has estrogen-like activity, it's worth a quick chat with your pharmacist or doctor.

References
  1. Henderson MC, Miranda CL, Stevens JF, et al. In vitro inhibition of human P450 enzymes by prenylated flavonoids from hops, Humulus lupulus. Xenobiotica 2000;30:235-51.. PubMed
  2. van Breemen RB, Chen L, Tonsing-Carter A, et al. Pharmacokinetic Interactions of a Hop Dietary Supplement with Drug Metabolism in Perimenopausal and Postmenopausal Women. J Agric Food Chem. 2020;68(18):5212-5220. PubMed
Minor

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES

3 of 3

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

Theoretically, hops extract might alter metabolism of CYP3A4 substrates; however, this effect may not be clinically significant.
Animal research suggests that specific constituents of hops, called lupulones, can induce hepatic CYP3A4 enzyme activity. However, a pharmacokinetic study in healthy postmenopausal patients with normal metabolism shows that taking a standardized extract of spent hops containing prenylated phenols, as 59.5 mg twice daily for 2 weeks, decreases the concentration of alprazolam, a CYP3A4 probe substrate, by 7.6%. This reduction is unlikely to be clinically relevant.
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 Activella combines two active hormones, estradiol and norethindrone, and both pass through a liver enzyme called CYP3A4 to be cleared from your body. The thinking here is that hops might nudge that enzyme to work a little faster, which could in theory lower your hormone levels slightly. If that happened, you might notice menopause symptoms creeping back, like hot flashes or irregular spotting.

Honestly though, the evidence behind this is very thin. It comes from lab and animal studies, and a human study using a hops extract changed a similar drug's level by less than 8 percent, which isn't enough to matter for most people. I wouldn't lose sleep over it, but if you plan to take hops regularly, mention it to your pharmacist or doctor so they can keep an eye on how you're feeling.

References
  1. Mannering, G. J., Shoeman, J. A., and Deloria, L. B. Identification of the antibiotic hops component, colupulone, as an inducer of hepatic cytochrome P-4503A in the mouse. Drug Metab Dispos 1992;20(2):142-147. DOI
  2. van Breemen RB, Chen L, Tonsing-Carter A, et al. Pharmacokinetic Interactions of a Hop Dietary Supplement with Drug Metabolism in Perimenopausal and Postmenopausal Women. J Agric Food Chem. 2020;68(18):5212-5220. 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

Hops Also Interacts With Other Medications

Hops has 288 moderate, 574 minor known drug interactions in our database — the Estradiol, Norethindrone Acetate 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 Hops

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

Everything else you take

See Every Supplement That Interacts With Estradiol, Norethindrone Acetate

This page covers Hops only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Estradiol, Norethindrone Acetate page lists 212 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 · 38 minor.

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

“Activella pairs estradiol with norethindrone as hormone therapy, and because the treatment depends on steady hormone levels in the blood, supplements that raise or lower those levels warrant real scrutiny. Three of the 212 interacting ingredients rate major, and all three hit that weak point: St.”

Reviewed by 2 · Jul 18, 2026

Open the Estradiol, Norethindrone Acetate interaction page

One more smart check

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

We hold 1,325 real supplement products containing Hops, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Hops. Your product may carry other ingredients that interact with Estradiol, Norethindrone Acetate too, on top of Hops — 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 Hops and Estradiol, Norethindrone Acetate 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 Hops
Top 25%

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

29 days ago today
Medication Estradiol, Norethindrone Acetate
Steady interest

#2,054 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 Hops

What is Hops?

Hops
  • Sleep problems and insomnia
  • Anxiety and restlessness
  • Menopausal symptoms
  • Mild digestive complaints
  • Flavoring in beer and food

Hops are most often used for sleep and mild anxiety, frequently combined with valerian, but the human evidence is limited and not very strong. They are generally well tolerated when used short-term, though they may cause drowsiness, and should be avoided during pregnancy and breastfeeding because their safety is unknown.

Read the full Hops monograph & all interactions
Keep checking

Other Drugs & Hops

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

0Major
288Moderate
574Minor
1,967No known interaction
Moderate

288 interactions

Showing 60 of 288 moderate interactions — see all 288 on the Hops page.

Minor

574 interactions

Showing 60 of 574 minor interactions — see all 574 on the Hops page.

No interaction 1,967 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 Hops and Estradiol, Norethindrone Acetate Together: Common Questions

Can you take Hops with Estradiol, Norethindrone Acetate?
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 Hops and Estradiol, Norethindrone Acetate?
Estradiol, Norethindrone Acetate belongs to more than one drug category, and Hops 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 Hops and Estradiol, Norethindrone Acetate 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.