Red Clover

Trifolium pratense

Efficacy

• Indications with possible efficacy:
  None
• Other indications with no proof of efficacy:
  Asthma
  Breast pain
  Bronchitis
  Burns (topically)
  Cardiovascular diseases
  Cough
  Eczema and psoriasis (topically)
  Osteoporosis
  Sexually transmitted diseases
  Symptoms of menopause - hot flashes (popular use)
  Whooping cough

Security

• Risk of Drug Interactions: Moderate
• Adverse Effects: Not Frequent

Description

Part of the plant used: flowers

Mostly known as a forage plant, red clover is extensively cultivated in North America and Europe. It has a very characteristic ball-like flower. This perennial plant has been valued for its medicinal properties for quite some time. The applicable part of the plant are the above-ground parts (leaves and flowers). Red clover has been associated with antispasmodic and expectorant activities. It is also thought to exert estrogenic activity due to its isoflavone constituents, and is thus used to relieved the symptoms of menopause.

Direction of use

There is no evidence that red clover is effective in any indication. However a standardized product called Promensil is said to effectively relieve the symptoms of menopause.

• Symptoms of menopause:
  Usual doses: 40 to 80 mg isoflavone per day

There is insufficient reliable information to conclude that red clover is effective in any other indication, including topically.

Precautions

• Side effects
  Red clover is not associated with any particular toxicity. It can however cause a rash-like reaction, muscle pain, headache or nausea in some people.
• Contraindications
  Avoid red clover if you have breast cancer or other hormone sensitive cancer.
• Interactions
  Because of the presence of coumarin derivatives, large doses of red clover may increase the effects of oral anticoagulants (Coumadin) and antiplatelet agents. Before taking red clover, check with your pharmacist to make sure that there are no drug interactions with your regular medication.
• Pregnancy and breastfeeding
  Because of its potential estrogenic activity, red clover is contraindicated in pregnant and lactating women.

Warning

In 2004, Canada adopted new regulations that control the manufacturing, packaging, labeling and importing of natural health products. The new regulations also include an adverse reaction reporting system. Products that conform to the regulation's criteria are identified with a natural product number (NPN) and can be legally sold in Canada. This number indicates that the product meets specific criteria for safety and purity, not that it is effective for any indication.

Medicinal plant contents vary naturally from plant to plant - just as fruits from the same package may vary in taste and texture. There is no standard to measure the active content of each plant. Thus, efficacy of natural products should be expected to vary from brand to brand as well as from bottle to bottle of the same brand.

For more information about the Natural Health Products Regulations, or to check if a product has been assessed, visit the Health Canada website at www.hc-sc.gc.ca/dhp-mps/prodnatur/index-eng.php.

References

1. Natural Medicine Comprehensive Database 1999
2. Natural Medicines Comprehensive Database, Therapeutic Research Faculty, 2010
3. Barnes J. et Al. Herbal Medicines, 2nd edition, Pharmaceutical Press, 2002
4. Natural therapeutics Pocket Guide 2000-2001 (Lexicomp)
5. Passeportsanté.net. Trèfle rouge. www.passeportsante.net
6. Rotblatt M. et Ziment I. Evidence-Based Herbal Medicine, Hanley & Belfus, 2002
7. The Review of Natural Products, 6th Edition, 2010