Red Clover (Trifolium pratense): Benefits, Dosage, Safety & Evidence

What is a herb–drug interaction?

A herb–drug interaction happens when a plant or supplement changes how a medication works in your body — making it stronger, weaker, or more likely to cause harm. Herbs contain active compounds that can speed up or slow down the enzymes and transporters your body uses to process drugs.

Why it matters

St. John's Wort can make birth control, antidepressants, and blood thinners less effective.

Garlic can increase bleeding risk with warfarin and other blood thinners (also ginkgo, ginger, and turmeric).

Kava can amplify sedation when taken with anxiety or sleep medications (also valerian).

The risk is highest for older adults, anyone taking several medications, and people with chronic conditions.

Always tell your doctor and pharmacist about every herb and supplement you take — and check below before combining.

Known Drug Interactions (2)

2 Moderate

Drug	Severity	Description
Tamoxifen	Moderate	Red clover isoflavones may interact with tamoxifen in estrogen-dependent conditions. The clinical significance is debated.
Warfarin (Coumadin)	Moderate	Red clover contains coumarin compounds that may enhance warfarin's anticoagulant effect.

This list reflects a curated subset of documented interactions and is not exhaustive. The absence of a drug here is not proof that it is safe to combine. Always confirm with a pharmacist or healthcare provider.

Frequently asked questions

How does red clover work for menopause symptoms?

Red clover contains isoflavones, specifically biochanin A, formononetin, genistein, and daidzein, which function as phytoestrogens. These compounds structurally resemble human estrogen and bind to estrogen receptors in the body. By acting as weak estrogens, they help modulate hormonal activity, which can alleviate common menopausal symptoms such as hot flashes and night sweats. Evidence Level: B.

Does red clover interact with medications like blood thinners?

Yes, red clover has known interactions. Due to its potential blood-thinning effects, it should be avoided by individuals taking anticoagulants like warfarin or antiplatelet drugs, as the combination increases the risk of bleeding. Additionally, because isoflavones affect estrogen levels, red clover may interfere with hormone replacement therapy (HRT) and oral contraceptives. Evidence Level: C.

What is the recommended dosage for red clover supplements?

For menopausal symptom relief, clinical studies typically utilize dosages providing 40 mg to 80 mg of total isoflavones daily, though some sources suggest up to 160 mg is safe. For traditional use, 2-3 cups of flower tea daily is common. Users should look for standardized extracts to ensure consistent isoflavone content. Evidence Level: B.

Is red clover safe to take during pregnancy?

No, red clover is considered unsafe during pregnancy and breastfeeding. The isoflavones in the plant exert estrogenic effects, which could theoretically disrupt hormonal balance during fetal development or harm the nursing infant. Women with hormone-sensitive conditions, such as breast or uterine cancer, should also avoid this herb. Evidence Level: C.

What are the traditional uses of red clover?

Historically, red clover was used as a 'blood purifier' to treat skin conditions like eczema and psoriasis. It was also a traditional remedy for respiratory ailments, including whooping cough and bronchitis. While modern use focuses on women's health, these traditional applications persist in herbal practice for supporting skin and respiratory health. Evidence Level: Traditional.

PubMed-compiled information sheet

This sheet was compiled from PubMed (NIH) abstracts using AI assistance. Every factual claim is cited to a real PubMed article (see the source list). It has not yet been human-reviewed — confirm with a healthcare provider before use.

Compiled from 30 PubMed articles · model: gemma4:31b

Summary

Red clover (Trifolium pratense) is a medicinal herb and forage legume used primarily to alleviate menopausal symptoms [PMID:11528359, PMID:33920485].

Background

Red clover (Trifolium pratense L.) is a protein-rich, perennial forage legume from the Fabaceae family [PMID:16645539, PMID:38283975, PMID:24500806].

Traditional uses

It is used as a traditional Chinese medicine and herbal medicine for regulating menopausal symptoms, heart problems, inflammatory disease, psoriasis, and cognitive deficits [PMID:36796742].

Active compounds

The plant contains isoflavones, including biochanin A, formononetin, genistein, and daidzein [PMID:37446841, PMID:40695042]. It also contains flavonolignans and isoflavonoid glycosides [PMID:34416305].

Mechanism of action

Isoflavonoids such as biochanin A and formononetin act as phytoestrogens to alleviate symptoms of estrogen deficiency [PMID:40695042]. Formononetin may inhibit α-glucosidase to reduce postprandial blood glucose [PMID:32115453] and has been shown to promote apoptosis and inhibit proliferation in various cancer cell models [PMID:31052435]. Red clover extracts may also modulate cellular iron homeostasis to inhibit ferroptotic cell death [PMID:36796742].

Clinical evidence

Evidence AMenopausal Hot Flushes

A meta-analysis of eight trials showed a statistically significant reduction in the daily incidence of hot flushes (WMD -1.73 per day) in women receiving red clover compared to placebo [PMID:33920485]. Another meta-analysis found it effective for 3-4 months (MD=-1.34), though effects did not persist at 12 months [PMID:25074017]. However, other reviews note inconsistent evidence or a lack of clear demonstrable benefit [PMID:11528359, PMID:16645539].

Evidence ABlood Lipid Profile

A systematic review and meta-analysis of 12 RCTs demonstrated a significant decrease in total cholesterol (WMD -12.34 mg/dl) and low-density lipoprotein cholesterol (WMD -10.61 mg/dl) in peri- and postmenopausal women [PMID:30269660].

Evidence DArterial Compliance

One study found a significant beneficial effect on arterial compliance [PMID:11528359].

Safety & adverse effects

Clinical evidence is presently lacking to support the safety of red clover isoflavone supplements in certain patients [PMID:16645539].

Evidence summary

The evidence for red clover in treating hot flushes is conflicting, though some meta-analyses show significant short-term reduction. There is stronger meta-analytic evidence for its effect on reducing total and LDL cholesterol in menopausal women.

PubMed sources

1.PMID: 33920485 (2021) — Evaluation of Clinical Meaningfulness of Red Clover (Trifolium pratense L.) Extract to Relieve Hot Flushes and Menopausal Symptoms in Peri- and Post-Menopausal Women: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. · Nutrients
2.PMID: 29403626 (2017) — A review of effective herbal medicines in controlling menopausal symptoms. · Electronic physician
3.PMID: 16988360 (2006) — Red clover (Trifolium pratense). · Methods in molecular biology (Clifton, N.J.)
4.PMID: 40488850 (2025) — Formononetin: pharmacological properties and therapeutic potential. · Naunyn-Schmiedeberg's archives of pharmacology
5.PMID: 19134450 (2008) — Red clover (Trifolium pratense). · Journal of the Society for Integrative Oncology

Red Clover

Sources & Citations

Calculate a safe dose of Red Clover

Black Cohosh

Dong Quai

Vitex

⚠️ Not Recommended During Pregnancy or Nursing

2 Known Drug Interactions — Some May Be Serious

Contraindications

Possible Side Effects

What is a herb–drug interaction?

Known Drug Interactions (2)

Frequently asked questions

Summary

Background

Traditional uses

Active compounds

Mechanism of action

Clinical evidence

Safety & adverse effects

Evidence summary

PubMed sources

Government sources

Red Clover

Sources & Citations

Calculate a safe dose of Red Clover

Related Herbs

Black Cohosh

Dong Quai

Vitex

⚠️ Not Recommended During Pregnancy or Nursing

2 Known Drug Interactions — Some May Be Serious

Contraindications

Possible Side Effects

What is a herb–drug interaction?

Known Drug Interactions (2)

Frequently asked questions

Summary

Background

Traditional uses

Active compounds

Mechanism of action

Clinical evidence

Safety & adverse effects

Evidence summary

PubMed sources

Government sources