Drug & supplement interaction

Peony + Oestrogen

Oestrogen brand name: Oestrogen.

Moderate Interaction
The bottom line Moderate

Oestrogen falls into 3 drug categories that Peony can interact with; the most serious is rated moderate. Theoretically, use of peony may increase the levels and clinical effects of drugs metabolized by CYP1A2.

Read the full interaction report
SeverityModerate
LikelihoodPossible
Interactions3
EvidenceD
What do Severity, Likelihood & Evidence mean?
Know someone taking this? Share
Interaction report

Peony and Oestrogen

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

Why Are There 3 Interactions?

Peony interacts with whole categories of medication. Oestrogen falls into 3 of those categories, so it can interact with Peony in 3 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 3

Why this applies to Oestrogen

Oestrogen falls under CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES — the group Peony interacts with.

Theoretically, use of peony may increase the levels and clinical effects of drugs metabolized by CYP1A2.
In vitro research shows that peony suppresses the metabolism of clozapine via weak-to-moderate inhibitory effects on CYP1A2 and 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

Here's the idea behind pairing peony with your estrogen. Part of how your body clears estrogen runs through a liver enzyme called CYP1A2. In test-tube studies, peony seems to gently slow that enzyme down. If that happened in real life, your estrogen could be cleared a little more slowly and build up, which might mean stronger effects or more of the usual estrogen side effects like breast tenderness, bloating, nausea, headaches, or spotting.

I want to be honest about the strength of this, though. This is theoretical, based only on lab work, and it has not been shown in actual people taking peony. So it's worth a quick mention to your pharmacist or doctor, but it isn't a reason to panic or stop anything on your own.

References
  1. Wang W, Tian DD, Zheng B, et al. Peony-glycyrrhiza decoction, an herbal preparation, inhibits clozapine metabolism via cytochrome P450s, but not flavin-containing monooxygenase in in vitro models. Drug Metab Dispos 2015;43(7):1147-53. PubMed
Moderate

ESTROGENS

2 of 3

Oestrogen also falls under ESTROGENS.

Theoretically, concomitant use of large amounts of peony might interfere with hormone replacement therapy and/or increase the risk for estrogen-related adverse effects.
In vitro and animal research shows that peony extract has estrogenic activity. Theoretically, peony might compete for estrogen receptors and/or cause additive estrogenic effects.
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 simple version: when you take estrogen as hormone therapy, you're adding estrogen to your body on purpose. Peony root contains plant compounds that act a little like estrogen too. So in theory, piling peony on top of your estrogen could nudge your total estrogen activity higher, or the two could bump into each other at the same receptors.

If estrogen effects ran higher, you might notice things like breast tenderness, bloating, nausea, headaches, or spotting. I want to be honest, though: this concern comes only from lab and animal studies, not from people, so it's very much a theoretical caution. Everyday culinary amounts are unlikely to matter; concentrated supplement doses are the real question. Before adding peony, please check with your pharmacist or doctor.

References
  1. Xu Y, Li X, Chen T, et al. Radix Paeoniae Alba increases serum estrogen level and up-regulates estrogen receptor expression in uterus and vagina of immature/ovariectomized mice. Phytother Res. 2019;33(1):117-29. [RETRACTED].
Moderate

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES

3 of 3

Oestrogen also falls under CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES.

Theoretically, use of peony may increase the levels and clinical effects of drugs metabolized by CYP3A4.
In vitro research shows that peony suppresses the metabolism of clozapine via weak-to-moderate inhibitory effects on CYP1A2 and 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 body relies on a liver enzyme called CYP3A4 to help break down and clear estrogen. Lab studies suggest peony root may gently slow that same enzyme down. If that happened in real life, estrogen could clear a little more slowly and build up, which might mean slightly stronger estrogen effects or side effects like breast tenderness, bloating, nausea, headaches, or breakthrough bleeding.

Here's the honest part: this is only a theoretical concern based on test-tube research, and it has never been reported in actual people. The effect on the enzyme was described as weak to moderate. So I wouldn't lose sleep over it, but it's worth a quick mention to your pharmacist or doctor before you pair peony with estrogen, especially if you start noticing new symptoms.

References
  1. Wang W, Tian DD, Zheng B, et al. Peony-glycyrrhiza decoction, an herbal preparation, inhibits clozapine metabolism via cytochrome P450s, but not flavin-containing monooxygenase in in vitro models. Drug Metab Dispos 2015;43(7):1147-53. 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

Peony Also Interacts With Other Medications

Peony has 810 moderate known drug interactions in our database — the Oestrogen 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 Peony

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

Everything else you take

See Every Supplement That Interacts With Oestrogen

This page covers Peony only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Oestrogen page lists 211 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 · 170 moderate · 38 minor.

From our pharmacist’s overview on the Oestrogen page

“Anyone taking oestrogen should read this page with real care, because the most serious entries can quietly push hormone levels up or wipe them out. Grapefruit blocks the liver enzyme that clears estrogen, raising levels and the risk of side effects, while St.”

Reviewed by 2 · Jul 18, 2026

Open the Oestrogen interaction page

One more smart check

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

We hold 71 real supplement products containing Peony, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Peony. Your product may carry other ingredients that interact with Oestrogen too, on top of Peony — 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 Peony and Oestrogen 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 Peony
Top 25%

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

29 days ago today
Medication Oestrogen
Steady interest

#2,050 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 Peony

What is Peony?

Peony
  • Menstrual cramps and irregular periods
  • Muscle cramps and spasms
  • Anxiety and stress
  • Inflammation and pain
  • Polycystic ovary syndrome (PCOS)

Peony root is a traditional Chinese medicine herb often used for menstrual problems, cramps, and inflammation, frequently as part of combination formulas. Human evidence for most uses is limited or preliminary, so it should not replace proven treatments. Talk to your pharmacist or doctor before using it, especially if you are pregnant, breastfeeding, or taking other medicines.

Read the full Peony monograph & all interactions
Keep checking

Other Drugs & Peony

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

0Major
810Moderate
0Minor
2,019No known interaction
Moderate

810 interactions

Showing 60 of 810 moderate interactions — see all 810 on the Peony page.

No interaction 2,019 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

Keep exploring
Pharmacist Counseling Corner

Taking Peony and Oestrogen Together: Common Questions

Can you take Peony with Oestrogen?
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 Peony and Oestrogen?
Oestrogen belongs to more than one drug category, and Peony 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 Peony and Oestrogen 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 Oestrogen and Peony?

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.