Red Clover Ingredients & Drug Interactions
by Herbal Terra
What is this page for?
First and foremost: checking Red Clover against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.
Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy
Red Clover is a dietary supplement by Herbal Terra with 1 active ingredient. Its ingredients are commonly taken for menopause symptoms (hot flashes), high cholesterol, bone health/osteoporosis.Based on those ingredients, 867 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Red Clover Seed Extract, Dry. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.
Check Your Meds Against Red Clover by Herbal Terra
Ask about any prescription or over-the-counter medication and we check it for interactions with Red Clover by Herbal Terra — and tell you which ingredient is responsible.
AI summaries are generated from our interaction database for education only — always confirm with your pharmacist. How we use AI
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HelloPharmacist Scorecard of Red Clover by Herbal Terra
Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.
What’s inside
Full disclosure
This liquid contains one active ingredient: red clover seed extract. Red clover is a plant whose extract supplies isoflavones—compounds with estrogen-like activity in the body.
The liquid also contains alcohol, water, and glycerin as inactive ingredients to preserve and deliver the extract.
Does it work?
Not established
The evidence for red clover isn't established in our data. The product has been studied for menopausal symptoms, osteoporosis, osteoarthritis, and male pattern baldness (androgenic alopecia), but current data gives us insufficient reliable evidence to rate how well it works for any of these uses.
How safe is it?
Well-documented data
Red clover is generally well tolerated in short-term use by healthy adults, but its estrogen-like effects mean you should be cautious if you're sensitive to hormones. The most common side effects reported are muscle pain, nausea, and vaginal spotting.
Because of its estrogenic activity and concerns about mammographic breast density in younger women, avoid this product during pregnancy and while breastfeeding—the safety data just isn't there to say it's okay.
Meds to double-check
Moderate interaction found
Before you start, double-check if you take estrogen-based drugs (hormone replacement therapy or birth control), tamoxifen, or methotrexate—these carry moderate interaction concerns. Also flag any blood thinners or antiplatelet drugs, and medications processed by your liver's CYP2C19, CYP2C9, or CYP3A4 enzymes, though real-world effects at typical doses appear low.
The bottom line
Scorecard at a glanceFully disclosed formula with no established evidence rating for its marketed use. Moderate medication interactions have been identified, and safety information is well characterized.
Red clover may be worth considering if you're looking into it for menopausal symptoms or bone health, though evidence is limited. If you take estrogen therapy, tamoxifen, methotrexate, or blood thinners, check with us first.
Pregnant or nursing? Skip this one.
Run your full medication list through the checker on this page.
Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI
Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated Dec 21, 2024.
This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed
General information
Key facts about Red Clover, straight from the product label.
| Brand | Herbal Terra |
|---|---|
| Barcode (UPC) | 7439500062097 |
| Net contents | 2 Fluid Ounce(s); 60 mL |
| Market status | On market |
| Date entered into DSLD | Dec 21, 2024 |
| DSLD ID | 325330 |
| Product type | Botanical |
| Supplement form | Liquid |
| Dietary claims / uses | All Other, Structure/Function |
| Intended target group(s) | Adult (18 - 50 Years), Gluten Free, Sugar Free |
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.
Supplement Facts
The label details for Red Clover by Herbal Terra, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| Red Clover Seed Extract, Dry | 983 mg | -- |
Other ingredients: Alcohol, Water, Glycerin
Tap any ingredient to jump to its full detail below.
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
Suggested/Recommended/Usage/Directions
Shake well before use. Adults take up to 30 drops (1 mL, one full squeeze of the dropper bulb) in 3-4 fl. oz. of juice or water up to 4 times a day.
Precautions
We recommend to seek expert medical advice before taking. May have contraindications and cause adverse reaction.
Consult a physician before giving to children under 18, before using during pregnancy, if nursing, or if you are on any medications.
Consult a physician before giving to children under 18, before using during pregnancy, if nursing, or if you are on any medications. Keep out of the reach of children!
Do not use if you are allergic to any ingredients.
Storage
Store in a cool, dry, dark place.
FDA Disclaimer Statement
This product has not been evaluated by the FDA and is not intended to diagnose, treat, cure or prevent any disease.
Formulation
cGMP Made in compliance with cGMP 21 CFR 111 in an FDA registered and inspected facility.
Sugar free
Expertly extracted 100% natural Premium product
Organic alcohol
No artificial ingredients, color additives, fillers or binders.
Natural Gluten free
Formula
Trifolium pratense
Organic alcohol
FDA Statement of Identity
Herbal Supplement
Seals/Symbols
Made in USA
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
Red Clover by Herbal Terra label
The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.
Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.
View the full label (PDF)The Ingredients in Red Clover by Herbal Terra
This is the 1 active ingredient this product is made of. Select it to open its full monograph.
Serving size1 mL Dosage formLiquid Servings per container60 Amounts shown are per serving.
Red Clover Seed Extract, Dry
Interacts with867 drugs
Red clover is a plant rich in isoflavones (plant compounds with weak estrogen-like activity) that is most often used for menopause symptoms like hot f...
Red Clover Seed Extract, Dry monograph & interactionsOther (inactive) ingredients: Alcohol, Water, Glycerin. These complete the product’s ingredient list but are not active constituents.
Red Clover by Herbal Terra Drug Interactions
HelloPharmacist Interaction Report
Red Clover by Herbal Terra contains one active ingredient—red clover seed extract—that interacts with a number of medications.
The most serious concerns are estrogen-based drugs (like hormone replacement therapy or birth control) and tamoxifen, a hormone-sensitive cancer medication. Red clover contains plant-based estrogens (phytoestrogens) that may compete with your body's natural estrogen and interfere with how these drugs work.
For tamoxifen specifically, there's theoretical concern that red clover could reduce its effectiveness, though animal evidence is mixed.
Read the full breakdown — every affected drug type, severity by severity
Red clover also raises a moderate concern with methotrexate, a medication used for psoriasis and certain cancers—there's a documented case of increased toxicity when the two were combined. Additionally, red clover may theoretically affect how your liver breaks down several classes of medications: drugs processed through CYP2C19, CYP2C9, and CYP3A4 enzymes, and blood thinners or antiplatelet drugs.
That said, small clinical studies testing CYP effects found no actual changes in drug levels at typical red clover doses.
Although lab research hints at anticoagulant effects, real-world studies haven't confirmed this risk. Altogether, these interactions span 857 individual medications.
We strongly recommend checking your exact prescriptions with the interaction checker below before starting this product.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against Red Clover?
Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.
Go to the checkerIngredients driving the most interactions
Individual Drug Interactions
The ingredients in Red Clover interact with 867 drugs. Click any drug to see the details.
1 of the 1 ingredient in Red Clover interact with drugs. Each result below shows which ingredient is responsible. Red Clover Seed Extract, Dry
Etonogestrel, Ethinyl EstradiolNuvaRing
How Etonogestrel, Ethinyl Estradiol interacts with Red Clover — through 1 ingredient. Tap an ingredient for the detail:
Red Clover Seed Extract, DryCytochrome P450 3a4 (cyp3a4) Substrates, Estrogens +1 Moderate
Interaction Summary
Theoretically, red clover might increase levels of drugs metabolized by CYP3A4; however, a small clinical study found no effect.
Read the full Red Clover Seed Extract, Dry + Etonogestrel, Ethinyl Estradiol interactionLevonorgestrel, Ethinyl EstradiolLogynon ED, Microgynon 30, Nordette, Ovranette, Quartette, Trinordiol +1 more
How Levonorgestrel, Ethinyl Estradiol interacts with Red Clover — through 1 ingredient. Tap an ingredient for the detail:
Red Clover Seed Extract, DryCytochrome P450 3a4 (cyp3a4) Substrates, Estrogens +1 Moderate
Interaction Summary
Theoretically, red clover might increase levels of drugs metabolized by CYP3A4; however, a small clinical study found no effect.
Read the full Red Clover Seed Extract, Dry + Levonorgestrel, Ethinyl Estradiol interactionMedroxyprogesterone Acetate, Oestrogens, ConjugatedPremique
How Medroxyprogesterone Acetate, Oestrogens, Conjugated interacts with Red Clover — through 1 ingredient. Tap an ingredient for the detail:
Red Clover Seed Extract, DryEstrogens, Cytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
Theoretically, concomitant use of large amounts of red clover might interfere with estrogen therapy.
Read the full Red Clover Seed Extract, Dry + Medroxyprogesterone Acetate, Oestrogens, Conjugated interactionMethotrexateOtrexup, Rasuvo, Reditrex, Rheumatrex
How Methotrexate interacts with Red Clover — through 1 ingredient. Tap an ingredient for the detail:
Red Clover Seed Extract, DryMethotrexate (trexall, Others) Moderate
Interaction Summary
Theoretically, red clover might increase the risk of methotrexate toxicity.
Read the full Red Clover Seed Extract, Dry + Methotrexate interactionMethotrexate SodiumXatmep
How Methotrexate Sodium interacts with Red Clover — through 1 ingredient. Tap an ingredient for the detail:
Red Clover Seed Extract, DryMethotrexate (trexall, Others) Moderate
Interaction Summary
Theoretically, red clover might increase the risk of methotrexate toxicity.
Read the full Red Clover Seed Extract, Dry + Methotrexate Sodium interactionNorelgestromin, Ethinyl EstradiolEvra, Ortho Evra
How Norelgestromin, Ethinyl Estradiol interacts with Red Clover — through 1 ingredient. Tap an ingredient for the detail:
Red Clover Seed Extract, DryEstrogens, Cytochrome P450 3a4 (cyp3a4) Substrates +1 Moderate
Interaction Summary
Theoretically, concomitant use of large amounts of red clover might interfere with estrogen therapy.
Read the full Red Clover Seed Extract, Dry + Norelgestromin, Ethinyl Estradiol interactionNorethindrone Acetate, Ethinyl Estradiol, Ferrous FumarateLoMinastrin FE, Minastrin 24 FE
How Norethindrone Acetate, Ethinyl Estradiol, Ferrous Fumarate interacts with Red Clover — through 1 ingredient. Tap an ingredient for the detail:
Red Clover Seed Extract, DryCytochrome P450 1a2 (cyp1a2) Substrates, Estrogens +1 Moderate
Interaction Summary
Theoretically, red clover might increase levels of drugs metabolized by CYP1A2; however, a small clinical study found no effect.
Read the full Red Clover Seed Extract, Dry + Norethindrone Acetate, Ethinyl Estradiol, Ferrous Fumarate interactionOestrogenOestrogen
How Oestrogen interacts with Red Clover — through 1 ingredient. Tap an ingredient for the detail:
Red Clover Seed Extract, DryCytochrome P450 3a4 (cyp3a4) Substrates, Cytochrome P450 1a2 (cyp1a2) Substrates +1 Moderate
Interaction Summary
Theoretically, red clover might increase levels of drugs metabolized by CYP3A4; however, a small clinical study found no effect.
Read the full Red Clover Seed Extract, Dry + Oestrogen interactionPrasterone (prescription Drug)Intrarosa
How Prasterone (prescription Drug) interacts with Red Clover — through 1 ingredient. Tap an ingredient for the detail:
Red Clover Seed Extract, DryEstrogens Moderate
Interaction Summary
Theoretically, concomitant use of large amounts of red clover might interfere with estrogen therapy.
Read the full Red Clover Seed Extract, Dry + Prasterone (prescription Drug) interactionRelugolix, Estradiol, Norethindrone AcetateMyfembree
How Relugolix, Estradiol, Norethindrone Acetate interacts with Red Clover — through 1 ingredient. Tap an ingredient for the detail:
Red Clover Seed Extract, DryCytochrome P450 3a4 (cyp3a4) Substrates, Cytochrome P450 1a2 (cyp1a2) Substrates +1 Moderate
Interaction Summary
Theoretically, red clover might increase levels of drugs metabolized by CYP3A4; however, a small clinical study found no effect.
Read the full Red Clover Seed Extract, Dry + Relugolix, Estradiol, Norethindrone Acetate interactionSegesterone Acetate, Ethinyl EstradiolAnnovera
How Segesterone Acetate, Ethinyl Estradiol interacts with Red Clover — through 1 ingredient. Tap an ingredient for the detail:
Red Clover Seed Extract, DryEstrogens, Cytochrome P450 1a2 (cyp1a2) Substrates +1 Moderate
Interaction Summary
Theoretically, concomitant use of large amounts of red clover might interfere with estrogen therapy.
Read the full Red Clover Seed Extract, Dry + Segesterone Acetate, Ethinyl Estradiol interactionTamoxifen CitrateNolvadex, Soltamox
How Tamoxifen Citrate interacts with Red Clover — through 1 ingredient. Tap an ingredient for the detail:
Red Clover Seed Extract, DryCytochrome P450 3a4 (cyp3a4) Substrates, Cytochrome P450 2c9 (cyp2c9) Substrates +1 Moderate
Interaction Summary
Theoretically, red clover might increase levels of drugs metabolized by CYP3A4; however, a small clinical study found no effect.
Read the full Red Clover Seed Extract, Dry + Tamoxifen Citrate interactionTiboloneLivial
How Tibolone interacts with Red Clover — through 1 ingredient. Tap an ingredient for the detail:
Red Clover Seed Extract, DryEstrogens Moderate
Interaction Summary
Theoretically, concomitant use of large amounts of red clover might interfere with estrogen therapy.
Read the full Red Clover Seed Extract, Dry + Tibolone interactionDrospirenone, Ethinyl Estradiol, LevomefolateBeyaz
How Drospirenone, Ethinyl Estradiol, Levomefolate interacts with Red Clover — through 1 ingredient. Tap an ingredient for the detail:
Red Clover Seed Extract, DryCytochrome P450 3a4 (cyp3a4) Substrates, Estrogens +1 Moderate
Interaction Summary
Theoretically, red clover might increase levels of drugs metabolized by CYP3A4; however, a small clinical study found no effect.
Read the full Red Clover Seed Extract, Dry + Drospirenone, Ethinyl Estradiol, Levomefolate interactionAdo-trastuzumab EmtansineKadcyla
How Ado-trastuzumab Emtansine interacts with Red Clover — through 1 ingredient. Tap an ingredient for the detail:
Red Clover Seed Extract, DryCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Theoretically, red clover might increase levels of drugs metabolized by CYP3A4; however, a small clinical study found no effect.
Read the full Red Clover Seed Extract, Dry + Ado-trastuzumab Emtansine interactionAbciximabReoPro
How Abciximab interacts with Red Clover — through 1 ingredient. Tap an ingredient for the detail:
Red Clover Seed Extract, DryAnticoagulant/antiplatelet Drugs Minor
Interaction Summary
Although some laboratory research suggests that red clover may have anticoagulant and antiplatelet activity, clinical research has not shown this effect.
Read the full Red Clover Seed Extract, Dry + Abciximab interactionAbemaciclibVerzenio
How Abemaciclib interacts with Red Clover — through 1 ingredient. Tap an ingredient for the detail:
Red Clover Seed Extract, DryCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Theoretically, red clover might increase levels of drugs metabolized by CYP3A4; however, a small clinical study found no effect.
Read the full Red Clover Seed Extract, Dry + Abemaciclib interactionAbiraterone
How Abiraterone interacts with Red Clover — through 1 ingredient. Tap an ingredient for the detail:
Red Clover Seed Extract, DryCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Theoretically, red clover might increase levels of drugs metabolized by CYP3A4; however, a small clinical study found no effect.
Read the full Red Clover Seed Extract, Dry + Abiraterone interactionAbiraterone AcetateYonsa, Zytiga
How Abiraterone Acetate interacts with Red Clover — through 1 ingredient. Tap an ingredient for the detail:
Red Clover Seed Extract, DryCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Theoretically, red clover might increase levels of drugs metabolized by CYP3A4; however, a small clinical study found no effect.
Read the full Red Clover Seed Extract, Dry + Abiraterone Acetate interactionAbrocitinibCibinqo
How Abrocitinib interacts with Red Clover — through 1 ingredient. Tap an ingredient for the detail:
Red Clover Seed Extract, DryCytochrome P450 2c19 (cyp2c19) Substrates, Cytochrome P450 2c9 (cyp2c9) Substrates +1 Minor
Interaction Summary
Theoretically, red clover might increase the levels and clinical effects of drugs metabolized by CYP2C19.
Read the full Red Clover Seed Extract, Dry + Abrocitinib interactionAcalabrutinibCalquence
How Acalabrutinib interacts with Red Clover — through 1 ingredient. Tap an ingredient for the detail:
Red Clover Seed Extract, DryCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Theoretically, red clover might increase levels of drugs metabolized by CYP3A4; however, a small clinical study found no effect.
Read the full Red Clover Seed Extract, Dry + Acalabrutinib interactionAcenocoumarolSintrom
How Acenocoumarol interacts with Red Clover — through 1 ingredient. Tap an ingredient for the detail:
Red Clover Seed Extract, DryAnticoagulant/antiplatelet Drugs Minor
Interaction Summary
Although some laboratory research suggests that red clover may have anticoagulant and antiplatelet activity, clinical research has not shown this effect.
Read the full Red Clover Seed Extract, Dry + Acenocoumarol interactionAcetaminophenChildren's Tylenol, Children's Tylenol Meltaways, Tylenol, Tylenol Ex Strength
How Acetaminophen interacts with Red Clover — through 1 ingredient. Tap an ingredient for the detail:
Red Clover Seed Extract, DryCytochrome P450 1a2 (cyp1a2) Substrates Minor
Interaction Summary
Theoretically, red clover might increase levels of drugs metabolized by CYP1A2; however, a small clinical study found no effect.
Read the full Red Clover Seed Extract, Dry + Acetaminophen interactionAcetaminophen, AspirinGemnisyn
How Acetaminophen, Aspirin interacts with Red Clover — through 1 ingredient. Tap an ingredient for the detail:
Red Clover Seed Extract, DryCytochrome P450 1a2 (cyp1a2) Substrates, Anticoagulant/antiplatelet Drugs Minor
Interaction Summary
Theoretically, red clover might increase levels of drugs metabolized by CYP1A2; however, a small clinical study found no effect.
Read the full Red Clover Seed Extract, Dry + Acetaminophen, Aspirin interactionAcetaminophen, Aspirin, CaffeineExcedrin, Excedrin Extra Strength, Excedrin Migraine
How Acetaminophen, Aspirin, Caffeine interacts with Red Clover — through 1 ingredient. Tap an ingredient for the detail:
Red Clover Seed Extract, DryAnticoagulant/antiplatelet Drugs, Cytochrome P450 1a2 (cyp1a2) Substrates +2 Minor
Interaction Summary
Although some laboratory research suggests that red clover may have anticoagulant and antiplatelet activity, clinical research has not shown this effect.
Read the full Red Clover Seed Extract, Dry + Acetaminophen, Aspirin, Caffeine interactionAcetaminophen, Brompheniramine, PhenylpropanolamineDimetapp Cold and Flu
How Acetaminophen, Brompheniramine, Phenylpropanolamine interacts with Red Clover — through 1 ingredient. Tap an ingredient for the detail:
Red Clover Seed Extract, DryCytochrome P450 1a2 (cyp1a2) Substrates Minor
Interaction Summary
Theoretically, red clover might increase levels of drugs metabolized by CYP1A2; however, a small clinical study found no effect.
Read the full Red Clover Seed Extract, Dry + Acetaminophen, Brompheniramine, Phenylpropanolamine interactionAcetaminophen, ButalbitalAxocet, Bancap, Bucet, Butex Forte, Esgic CF, Orbivan CF +5 more
How Acetaminophen, Butalbital interacts with Red Clover — through 1 ingredient. Tap an ingredient for the detail:
Red Clover Seed Extract, DryCytochrome P450 1a2 (cyp1a2) Substrates Minor
Interaction Summary
Theoretically, red clover might increase levels of drugs metabolized by CYP1A2; however, a small clinical study found no effect.
Read the full Red Clover Seed Extract, Dry + Acetaminophen, Butalbital interactionAcetaminophen, Butalbital, CaffeineEsgic, Esgic Plus, Fiogesic, Fioricet, Repan, Tecnal +1 more
How Acetaminophen, Butalbital, Caffeine interacts with Red Clover — through 1 ingredient. Tap an ingredient for the detail:
Red Clover Seed Extract, DryCytochrome P450 1a2 (cyp1a2) Substrates, Cytochrome P450 3a4 (cyp3a4) Substrates +1 Minor
Interaction Summary
Theoretically, red clover might increase levels of drugs metabolized by CYP1A2; however, a small clinical study found no effect.
Read the full Red Clover Seed Extract, Dry + Acetaminophen, Butalbital, Caffeine interactionAcetaminophen, Butalbital, Caffeine, CodeineEsgic with Codeine, Fioricet w/ Codeine
How Acetaminophen, Butalbital, Caffeine, Codeine interacts with Red Clover — through 1 ingredient. Tap an ingredient for the detail:
Red Clover Seed Extract, DryCaffeine, Cytochrome P450 1a2 (cyp1a2) Substrates +1 Minor
Interaction Summary
Theoretically, soy might reduce the clearance of caffeine; however, a small clinical study found no effect.
Read the full Red Clover Seed Extract, Dry + Acetaminophen, Butalbital, Caffeine, Codeine interactionAcetaminophen, Butalbital, CodeineBancap w/ Codeine
How Acetaminophen, Butalbital, Codeine interacts with Red Clover — through 1 ingredient. Tap an ingredient for the detail:
Red Clover Seed Extract, DryCytochrome P450 1a2 (cyp1a2) Substrates Minor
Interaction Summary
Theoretically, red clover might increase levels of drugs metabolized by CYP1A2; however, a small clinical study found no effect.
Read the full Red Clover Seed Extract, Dry + Acetaminophen, Butalbital, Codeine interactionEach ingredient & the kinds of drugs it affects
For each ingredient in Red Clover with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.
Red Clover Seed Extract, Dry
Estrogens
Theoretically, concomitant use of large amounts of red clover might interfere with estrogen therapy.
Red clover contains phytoestrogens which might have estrogenic activity in some people. Theoretically, red clover might compete for estrogen receptors and interfere with estrogen-containing drug therapy.
Methotrexate (Trexall, Others)
Theoretically, red clover might increase the risk of methotrexate toxicity.
In a case report, a 52-year-old female receiving weekly methotrexate injections for psoriasis developed symptoms of methotrexate toxicity, including severe vomiting and epigastric pain, after three days of taking red clover 430 mg daily. Toxicity resolved after red clover was discontinued. However, no liver function tests or methotrexate levels were reported.
Tamoxifen (Nolvadex)
Theoretically, the phytoestrogens in red clover might interfere with tamoxifen.
In vitro and animal research suggests that genistein, a constituent of red clover, might antagonize the antitumor effects of tamoxifen. However, there is some evidence from an animal study that red clover does not reduce the efficacy of tamoxifen. Until more is known, tell patients taking tamoxifen to avoid red clover.
Anticoagulant/Antiplatelet Drugs
Although some laboratory research suggests that red clover may have anticoagulant and antiplatelet activity, clinical research has not shown this effect.
In vitro research suggests that genistein in red clover has antiplatelet effects, and historically, red clover was thought to have anticoagulant effects due to its coumarin content. However, some experts state that this is unlikely as most natural coumarins have not been shown to have anticoagulant effects, and their content in red clover is low. Additionally, some clinical research in postmenopausal patients found no effect on coagulation or prothrombin time with the use of red clover flowering tops 378 mg daily for 12 months or red clover isoflavone (Rimostil) 50 mg daily for 2 years.
Caffeine
Theoretically, soy might reduce the clearance of caffeine; however, a small clinical study found no effect.
Red clover contains genistein. Taking genistein 1 gram daily for 14 days seems to inhibit caffeine clearance and metabolism in healthy females. However, this effect does not seem to occur with the lower amounts of genistein found in red clover. A clinical study in healthy postmenopausal individuals shows that taking red clover capsules standardized to contain 60 mg isoflavones twice daily for 14 days does not affect the pharmacokinetics of caffeine.
Cytochrome P450 1A2 (Cyp1A2) Substrates
Theoretically, red clover might increase levels of drugs metabolized by CYP1A2; however, a small clinical study found no effect.
In vitro evidence shows that red clover inhibits CYP1A2. However, a clinical study in healthy postmenopausal individuals shows that taking red clover capsules standardized to contain 60 mg isoflavones twice daily for 14 days does not affect the pharmacokinetics of caffeine, a CYP1A2 probe substrate.
Cytochrome P450 2C19 (Cyp2C19) Substrates
Theoretically, red clover might increase the levels and clinical effects of drugs metabolized by CYP2C19.
In vitro evidence suggests that red clover weakly inhibits CYP2C19. This interaction has not been reported in humans.
Cytochrome P450 2C9 (Cyp2C9) Substrates
Theoretically, red clover might increase levels of drugs metabolized by CYP2C9; however, a small clinical study found no effect.
In vitro evidence suggests that red clover might inhibit CYP2C9. However, a clinical study in healthy postmenopausal individuals shows that taking red clover capsules standardized to contain 60 mg isoflavones twice daily for 14 days does not affect the pharmacokinetics of tolbutamide, a CYP2C9 probe substrate.
Cytochrome P450 3A4 (Cyp3A4) Substrates
Theoretically, red clover might increase levels of drugs metabolized by CYP3A4; however, a small clinical study found no effect.
In vitro evidence shows that red clover might inhibit CYP3A4 isoenzymes. However, a clinical study in healthy postmenopausal individuals shows that taking red clover capsules standardized to contain 60 mg isoflavones twice daily for 14 days does not affect the pharmacokinetics of alprazolam, a CYP3A4 probe substrate.
Brand information
Manufacturer and brand details for Red Clover, from the product label.
Herbal Terra
See all Herbal Terra products- Name
- Herbal Terra LLC
- Phone Number
- +18083857868
- Web Address
- herbalterra.com
Red Clover by Herbal Terra: Common Questions
Does Red Clover by Herbal Terra interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
Can I take red clover if I'm on birth control or hormone replacement therapy?
Is red clover safe to take while pregnant or breastfeeding?
What are the most common side effects?
Does red clover actually work for menopausal symptoms or osteoporosis?
If I take a blood thinner like warfarin, is this safe?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if Red Clover is safe with your meds?
Our pharmacists answer your medication & supplement questions — free.
Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.
The Full Monographs Behind Red Clover’s Ingredients
Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.
Sources & How We Checked
Red Clover's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.
- NIH Dietary Supplement Label Database (DSLD) — The official product label on file for this supplement.
- Natural Medicines (Therapeutic Research Center) — Evidence-graded clinical reference behind the ingredient interaction data.
Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.
The 24 references behind this product’s interaction data
Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.
Red Clover 24 references
- Kurzer MS, Xu X. Dietary phytoestrogens. Annu Rev Nutr 1997;17:353-81. PubMed
- Electronic Code of Federal Regulations. Title 21. Part 182 -- Substances Generally Recognized As Safe. Available at: https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?CFRPart=182
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