Red Clover Flower Ingredients & Drug Interactions
by Cedar Bear
What is this page for?
First and foremost: checking Red Clover Flower 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 Flower is a dietary supplement by Cedar Bear 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. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.
Check Your Meds Against Red Clover Flower by Cedar Bear
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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 Flower by Cedar Bear
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
Low disclosure
This product contains one active ingredient: red clover flower. Red clover is a plant whose flower contains naturally occurring compounds called phytoestrogens — plant substances that mimic estrogen in the body.
The liquid is suspended in vegetable glycerin and purified water.
Does it work?
Couldn't assess
The evidence for red clover's effectiveness is not established in the data we hold. We do not have reliable evidence to rate it for menopausal symptoms, osteoporosis, osteoarthritis, or hair loss (androgenic alopecia).
If you're considering it for any of these uses, it's worth a conversation with your doctor or pharmacist about what the current research actually shows.
How safe is it?
Well-documented data
Red clover is generally well tolerated short-term in healthy adults, but its estrogen-like effects mean certain people need to be cautious. The most common side effects reported are muscle pain, nausea, and vaginal spotting.
There has also been some concern about whether red clover might increase breast density in younger women, though a review of clinical trials suggests any increase is modest and confined to premenopausal individuals. Pregnancy and breastfeeding: Safety data advises against red clover during pregnancy because of its estrogen-like effects.
There isn't enough safety information for breastfeeding — talk with your doctor or pharmacist for personalized advice if you're nursing.
Meds to double-check
Moderate interaction found
Before taking this product, double-check with your doctor or pharmacist if you take estrogen-containing medications, methotrexate, or tamoxifen — these have Moderate-severity interactions. Also confirm any drugs your liver metabolizes through CYP1A2, CYP2C19, CYP2C9, or CYP3A4 enzymes, and blood thinners or antiplatelet drugs like aspirin, which have Minor interactions.
Altogether, these interactions span 868 individual medications.
The bottom line
Scorecard at a glanceFormula with limited ingredient disclosure with no assessable stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.
Red Clover Flower may be worth considering if you're exploring options for menopausal symptoms or bone health, but the evidence for its effectiveness isn't solid yet. If you take estrogen therapy, methotrexate, tamoxifen, or drugs processed through your liver's CYP enzymes, you should check with your own doctor or pharmacist before starting this product.
Pregnant and breastfeeding people should avoid it or discuss it with their healthcare provider first.
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 Nov 21, 2020.
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 Flower, straight from the product label.
| Brand | Cedar Bear |
|---|---|
| Barcode (UPC) | 834711000666 |
| Net contents | 30 mL; 1 fl. Oz. |
| Market status | On market |
| Date entered into DSLD | Nov 21, 2020 |
| DSLD ID | 239309 |
| Product type | Botanical |
| Supplement form | Liquid |
| Dietary claims / uses | All Other, Structure/Function |
| Intended target group(s) | Vegan, Vegetarian, Adult (18 - 50 Years), Kosher, 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 Flower by Cedar Bear, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| Proprietary Blend | 0.5 mL | -- |
| Red Clover | 0 NP | -- |
Other ingredients: USP Grade Vegetable Glycerine, purified Water
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.
Formulation
Manufactured in the USA
True Alcohol Free Sugar Free Gluten Free
Vegan
Suggested/Recommended/Usage/Directions
Suggested Use: .5 mL (10 drops) 1 to 3 times a day, or as needed. Shake well.
Precautions
Note: Consult your physician before use.
FDA Disclaimer Statement
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.
Seals/Symbols
GMP Good Manufacturing Practices K (Kosher)
Formula
K (Kosher)
Trifolium pratense
General Statements
Herbal single
FDA Statement of Identity
Dietary Supplement
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
Red Clover Flower by Cedar Bear 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 Flower by Cedar Bear
This is the 1 active ingredient this product is made of. Select it to open its full monograph.
Serving size0.5 mL Dosage formLiquid Servings per container60 Amounts shown are per serving.
Proprietary Blend
Other (inactive) ingredients: USP Grade Vegetable Glycerine, Purified Water. These complete the product’s ingredient list but are not active constituents.
Red Clover Flower by Cedar Bear Drug Interactions
HelloPharmacist Interaction Report
Red Clover Flower by Cedar Bear interacts with several medication types, most notably estrogens, methotrexate, and tamoxifen.
The most serious interactions are Moderate in severity: estrogen-containing drugs may have reduced effectiveness because red clover's plant estrogens (phytoestrogens) can compete for estrogen receptors in your body. Methotrexate toxicity is also a Moderate concern — one case report documented severe nausea and stomach pain after a patient took red clover while on weekly methotrexate injections for psoriasis.
Tamoxifen's cancer-fighting effects may similarly be weakened by red clover's phytoestrogens, though animal evidence on this is mixed.
Read the full breakdown — every affected drug type, severity by severity
Red clover also has Minor interactions with several drug-metabolizing enzymes in your liver (CYP1A2, CYP2C19, CYP2C9, and CYP3A4 substrates). In theory it could raise blood levels of drugs processed through these pathways, though small clinical studies so far have not detected this effect.
It may also theoretically affect blood thinners and antiplatelet drugs (aspirin-like medications), but clinical research has not confirmed this.
Alone among its checked ingredients, no other active ingredients are present to screen. Use the medication checker on this page to confirm whether any of your prescriptions fall into these categories before you start.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against Red Clover Flower?
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 Flower interact with 867 drugs. Click any drug to see the details.
1 of the 1 ingredient in Red Clover Flower interact with drugs. Each result below shows which ingredient is responsible. Red Clover
Bazedoxifene Acetate, Conjugated EstrogensDuavee
How Bazedoxifene Acetate, Conjugated Estrogens interacts with Red Clover Flower — through 1 ingredient. Tap an ingredient for the detail:
Red CloverEstrogens, 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 + Bazedoxifene Acetate, Conjugated Estrogens interactionConjugated EstrogensCenestin, Enjuvia, Premarin, Premarin Vaginal Cream
How Conjugated Estrogens interacts with Red Clover Flower — through 1 ingredient. Tap an ingredient for the detail:
Red CloverCytochrome P450 3a4 (cyp3a4) Substrates, Estrogens 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 + Conjugated Estrogens interactionConjugated Estrogens, Medroxyprogesterone AcetatePremplus, Prempro
How Conjugated Estrogens, Medroxyprogesterone Acetate interacts with Red Clover Flower — through 1 ingredient. Tap an ingredient for the detail:
Red CloverEstrogens, 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 + Conjugated Estrogens, Medroxyprogesterone Acetate interactionConjugated Estrogens, MeprobamatePMB 200, PMB 400
How Conjugated Estrogens, Meprobamate interacts with Red Clover Flower — through 1 ingredient. Tap an ingredient for the detail:
Red CloverCytochrome P450 3a4 (cyp3a4) Substrates, Estrogens 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 + Conjugated Estrogens, Meprobamate interactionConjugated Estrogens, MethyltestosteronePremarin with Methyltestosterone
How Conjugated Estrogens, Methyltestosterone interacts with Red Clover Flower — through 1 ingredient. Tap an ingredient for the detail:
Red CloverEstrogens, 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 + Conjugated Estrogens, Methyltestosterone interactionCyproterone Acetate, Ethinyl EstradiolDiane-35, Dianette
How Cyproterone Acetate, Ethinyl Estradiol interacts with Red Clover Flower — through 1 ingredient. Tap an ingredient for the detail:
Red CloverCytochrome 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 + Cyproterone Acetate, Ethinyl Estradiol interactionDesogestrel, Ethinyl EstradiolDesogen, Marvelon, Marvelon 21, Marvelon 28, Mircette, Ortho-Cept +2 more
How Desogestrel, Ethinyl Estradiol interacts with Red Clover Flower — through 1 ingredient. Tap an ingredient for the detail:
Red CloverCytochrome P450 1a2 (cyp1a2) Substrates, Cytochrome P450 3a4 (cyp3a4) Substrates +2 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 + Desogestrel, Ethinyl Estradiol interactionDrospirenone, EstetrolNextstellis
How Drospirenone, Estetrol interacts with Red Clover Flower — through 1 ingredient. Tap an ingredient for the detail:
Red CloverCytochrome 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 + Drospirenone, Estetrol interactionDrospirenone, Ethinyl EstradiolAngeliq, Gianvi, Yasmin
How Drospirenone, Ethinyl Estradiol interacts with Red Clover Flower — through 1 ingredient. Tap an ingredient for the detail:
Red CloverCytochrome 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 + Drospirenone, Ethinyl Estradiol interactionEsterified EstrogensEstratab, Menest
How Esterified Estrogens interacts with Red Clover Flower — through 1 ingredient. Tap an ingredient for the detail:
Red CloverEstrogens, 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 + Esterified Estrogens interactionEsterified Estrogens, MethyltestosteroneEstratest
How Esterified Estrogens, Methyltestosterone interacts with Red Clover Flower — through 1 ingredient. Tap an ingredient for the detail:
Red CloverCytochrome P450 3a4 (cyp3a4) Substrates, Estrogens 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 + Esterified Estrogens, Methyltestosterone interactionEstradiolDivigel, Elestrin, Estrace, Estraderm, Estring, Evamist +6 more
How Estradiol interacts with Red Clover Flower — through 1 ingredient. Tap an ingredient for the detail:
Red CloverEstrogens, 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 + Estradiol interactionEstradiol, MedroxyprogesteroneDivitren
How Estradiol, Medroxyprogesterone interacts with Red Clover Flower — through 1 ingredient. Tap an ingredient for the detail:
Red CloverCytochrome 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 + Estradiol, Medroxyprogesterone interactionEstradiol, Norethindrone AcetateActivella
How Estradiol, Norethindrone Acetate interacts with Red Clover Flower — through 1 ingredient. Tap an ingredient for the detail:
Red CloverCytochrome 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 + Estradiol, Norethindrone Acetate interactionEstradiol, NorgestimateOrtho-Prefest
How Estradiol, Norgestimate interacts with Red Clover Flower — through 1 ingredient. Tap an ingredient for the detail:
Red CloverEstrogens, Cytochrome P450 1a2 (cyp1a2) Substrates Moderate
Interaction Summary
Theoretically, concomitant use of large amounts of red clover might interfere with estrogen therapy.
Read the full Red Clover + Estradiol, Norgestimate interactionEstradiol, ProgesteroneBijuvanda
How Estradiol, Progesterone interacts with Red Clover Flower — through 1 ingredient. Tap an ingredient for the detail:
Red CloverCytochrome P450 1a2 (cyp1a2) Substrates, Cytochrome P450 3a4 (cyp3a4) Substrates +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 + Estradiol, Progesterone interactionEstrogenEstrogen
How Estrogen interacts with Red Clover Flower — through 1 ingredient. Tap an ingredient for the detail:
Red CloverEstrogens, 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 + Estrogen interactionEstroneOrtho-Est
How Estrone interacts with Red Clover Flower — through 1 ingredient. Tap an ingredient for the detail:
Red CloverEstrogens Moderate
Interaction Summary
Theoretically, concomitant use of large amounts of red clover might interfere with estrogen therapy.
Read the full Red Clover + Estrone interactionEstropipateOgen, Ortho EST
How Estropipate interacts with Red Clover Flower — through 1 ingredient. Tap an ingredient for the detail:
Red CloverEstrogens Moderate
Interaction Summary
Theoretically, concomitant use of large amounts of red clover might interfere with estrogen therapy.
Read the full Red Clover + Estropipate interactionEthiny Estradiol, LevonorgestrelLogynon, Microgynon 30 ED
How Ethiny Estradiol, Levonorgestrel interacts with Red Clover Flower — through 1 ingredient. Tap an ingredient for the detail:
Red CloverCytochrome 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 + Ethiny Estradiol, Levonorgestrel interactionEthinyl EstradiolEstinyl
How Ethinyl Estradiol interacts with Red Clover Flower — through 1 ingredient. Tap an ingredient for the detail:
Red CloverCytochrome P450 1a2 (cyp1a2) Substrates, Cytochrome P450 3a4 (cyp3a4) Substrates +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 + Ethinyl Estradiol interactionEthinyl Estradiol, DesogestrelApri, Cesia, Cyclessa, Gedarel, Kariva, Linessa +4 more
How Ethinyl Estradiol, Desogestrel interacts with Red Clover Flower — through 1 ingredient. Tap an ingredient for the detail:
Red CloverCytochrome P450 2c9 (cyp2c9) Substrates, Estrogens +2 Moderate
Interaction Summary
Theoretically, red clover might increase levels of drugs metabolized by CYP2C9; however, a small clinical study found no effect.
Read the full Red Clover + Ethinyl Estradiol, Desogestrel interactionEthinyl Estradiol, DrospirenoneYaz
How Ethinyl Estradiol, Drospirenone interacts with Red Clover Flower — through 1 ingredient. Tap an ingredient for the detail:
Red CloverCytochrome 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 + Ethinyl Estradiol, Drospirenone interactionEthinyl Estradiol, Ethynodiol DiacetateDemulen 1/35, Demulen 1/50, Demulen Compack, Kelnor 1/35, Zovia, Zovia 1/35 +1 more
How Ethinyl Estradiol, Ethynodiol Diacetate interacts with Red Clover Flower — through 1 ingredient. Tap an ingredient for the detail:
Red CloverEstrogens, 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 + Ethinyl Estradiol, Ethynodiol Diacetate interactionEthinyl Estradiol, LevonorgestrelAlesse, Alesse 21, Alesse 28, Aviane, Enpresse, Jolessa +18 more
How Ethinyl Estradiol, Levonorgestrel interacts with Red Clover Flower — through 1 ingredient. Tap an ingredient for the detail:
Red CloverCytochrome 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 + Ethinyl Estradiol, Levonorgestrel interactionEthinyl Estradiol, NorethindroneAranelle, Brevicon, Brevicon .5/35 21 day, Brevicon .5/35 28 day, Brevicon 1/35 21 day, Brevicon 1/35 28 day +50 more
How Ethinyl Estradiol, Norethindrone interacts with Red Clover Flower — through 1 ingredient. Tap an ingredient for the detail:
Red CloverEstrogens, 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 + Ethinyl Estradiol, Norethindrone interactionEthinyl Estradiol, Norethindrone, Ferrous FumarateEstrostep Fe, Femcon FE, Junel Fe 1.5/30, Loestrin Fe, Loestrin Fe 1.5/30, Loestrin Fe 1/20 +3 more
How Ethinyl Estradiol, Norethindrone, Ferrous Fumarate interacts with Red Clover Flower — through 1 ingredient. Tap an ingredient for the detail:
Red CloverCytochrome 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 + Ethinyl Estradiol, Norethindrone, Ferrous Fumarate interactionEthinyl Estradiol, NorgestimateCilest, Mononessa, Ortho Tri-Cyclen 28, Ortho Tri-Cyclen Lo, Ortho Tri-Cylcen, Ortho-Cyclen +5 more
How Ethinyl Estradiol, Norgestimate interacts with Red Clover Flower — through 1 ingredient. Tap an ingredient for the detail:
Red CloverEstrogens, 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 + Ethinyl Estradiol, Norgestimate interactionEthinyl Estradiol, NorgestrelCryselle, Lo/Ovral, Low-Ogestrel, Ogestrel 0.5/50, Ovral
How Ethinyl Estradiol, Norgestrel interacts with Red Clover Flower — through 1 ingredient. Tap an ingredient for the detail:
Red CloverCytochrome 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 + Ethinyl Estradiol, Norgestrel interactionEthinyl Estradiol, LevonogestrelLybrel
How Ethinyl Estradiol, Levonogestrel interacts with Red Clover Flower — through 1 ingredient. Tap an ingredient for the detail:
Red CloverEstrogens, 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 + Ethinyl Estradiol, Levonogestrel interactionEach ingredient & the kinds of drugs it affects
For each ingredient in Red Clover Flower 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
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 Flower, from the product label.
Cedar Bear
See all Cedar Bear products- Name
- Cedar Bear Naturales INC
- Street Address
- PO Box 158
- City
- Roosevelt
- State
- UT
- ZipCode
- 84066
- Phone Number
- 1-888-854-3727
- Web Address
- Cedarbear.com
Red Clover Flower by Cedar Bear: Common Questions
Does Red Clover Flower by Cedar Bear interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
Can I take this if I'm on hormone replacement therapy or birth control?
What side effects should I watch for?
Is there evidence that red clover actually works for hot flashes or osteoporosis?
Is it safe to take while pregnant?
What exactly are the phytoestrogens in red clover?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if Red Clover Flower 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 Flower’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 Flower'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
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