Drug & supplement interaction

Jequirity + Estradiol

Estradiol brand names: Estrace, Gynodiol, Vagifem, Estring, Vivelle, and others.

Minor Interaction
The bottom line Minor

Jequirity has a minor interaction with Estradiol. In vitro research shows that jequirity extract inhibits CYP3A4 enzymes.

Read the full interaction report
SeverityMinor
LikelihoodUnlikely
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Jequirity and Estradiol

Here is the interaction we found between these two, with the evidence behind it.

Minor

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES

Why this applies to Estradiol

Estradiol falls under CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES — the group Jequirity interacts with.

In vitro research shows that jequirity extract inhibits CYP3A4 enzymes. Theoretically, taking jequirity may inhibit the metabolism of CYP3A4 substrates.
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

First, the most important thing: jequirity seeds are extremely poisonous and should never be taken as a supplement or remedy. The toxin in them, abrin, can be deadly. So my real advice here is to steer clear of jequirity entirely, regardless of any medication.

That said, here's the interaction on file. Your body uses an enzyme called CYP3A4 to help break down estradiol. Lab studies (just test-tube work, not people) suggest jequirity may slow that enzyme down. In theory, that could let estradiol build up a bit, which might mean more estrogen-type effects like breast tenderness, bloating, nausea, or spotting. Estradiol is not a prodrug, so slowing its breakdown would tend to increase its effect, not weaken it. The evidence is weak and this is rated unlikely, but please check with your pharmacist or doctor before combining anything new.

References
  1. Ai C, Miao X, Wang L, He J. Discovery and Activity Evaluation of the Inhibitory Effect of Four Kinds Traditional Chinese Medicine Extracts on the CYP3A4 Enzyme. Comb Chem High Throughput Screen 2022.

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

Jequirity Also Interacts With Other Medications

Jequirity has 208 moderate, 602 minor known drug interactions in our database — the Estradiol one above is one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Jequirity

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

Everything else you take

See Every Supplement That Interacts With Estradiol

This page covers Jequirity only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Estradiol page lists 213 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 · 172 moderate · 38 minor.

From our pharmacist’s overview on the Estradiol page

“Estradiol (Estrace, Vivelle, Vagifem, and other brands) is estrogen therapy, and its interaction list deserves careful reading, especially the three entries rated major. Grapefruit can push estradiol levels higher, St.”

Reviewed by 2 · Jul 18, 2026

Open the Estradiol interaction page

How much people look this up

Where Jequirity and Estradiol 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 Jequirity
Steady interest

#1,182 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Estradiol
Top 25%

#380 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 Jequirity

What is Jequirity?

Jequirity
  • Asthma and cough
  • Fever
  • Sore throat and bronchitis
  • Liver complaints (hepatitis)
  • Constipation
  • Traditional infectious-disease remedies

Jequirity (Abrus precatorius) is a tropical plant whose bright red, black-tipped seeds contain abrin, one of the most toxic plant proteins known. Despite a long history in traditional medicine, the seeds are dangerously poisonous and there is no reliable evidence that it is safe or effective. It should not be used as a supplement or medicine.

Read the full Jequirity monograph & all interactions
Keep checking

Other Drugs & Jequirity

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

0Major
208Moderate
602Minor
2,019No known interaction
Moderate

208 interactions

Showing 60 of 208 moderate interactions — see all 208 on the Jequirity page.

Minor

602 interactions

Showing 60 of 602 minor interactions — see all 602 on the Jequirity 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

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Pharmacist Counseling Corner

Taking Jequirity and Estradiol Together: Common Questions

Can you take Jequirity with Estradiol?
There is only a minor interaction, which is usually not serious. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Jequirity and Estradiol interaction?
We rate it Minor. This interaction is generally not clinically significant, but it remains worth noting and discussing with your pharmacist.

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.