Yarrow

 


Clinical Overview

Use


Limited clinical studies are available.

Dosing


Traditionally, yarrow herb at 4.5 g/day has been utilized for various conditions. However, there is a lack of quality clinical studies to substantiate this dosing.

Contraindications


Yarrow use is contraindicated in individuals with known allergies to any members of the Aster family. Data regarding contraindications in epilepsy are not available.

Pregnancy/Lactation


Avoid use due to documented adverse effects.

Interactions


No well-documented interactions.

Adverse Reactions


Contact dermatitis is the most commonly reported adverse reaction, with potential anticholinergic effects associated with high doses.

Toxicology


Yarrow is generally not considered toxic, but reports suggest an antispermatogenic effect. Safety data are insufficient to support its use in cosmetic products.

Scientific Family


Asteraceae (daisy)
Compositae (aster)

Botany


The name yarrow applies to around 80 species of daisy plants native to the north temperate zone. A. millefolium L. has finely divided leaves and white, pink, or red flowers. It belongs to the Aster family, which includes aster, chamomile, chrysanthemum, feverfew, ragweed, sunflower, and tansy.

History


The use of yarrow in food and medicine dates back to at least 1200 BC. The genus name Achillea is derived from the Greek myth of Achilles, who carried A. millefolium into battle. Yarrow leaves have been used for tea, salads, and medicinal purposes in various cultures.


Turmeric, Ginkgo Biloba

Chemistry


The constituents of yarrow, including essential oils, flavonoids, tannins, and sesquiterpene lactones, have been reviewed in detail.

Uses and Pharmacology

  1. Anti-inflammatory Activity
  • Animal Data: Demonstrated in animal and in vitro studies.
  • Clinical Data: Limited evidence in clinical trials for conditions like ulcerative colitis and irritable bowel syndrome.
  1. Antimicrobial/Antiprotozoal Activity
  • In Vitro Studies: Yarrow essential oil shows limited antibacterial and antiviral activity. Some inhibitory effects on inflammation and reactive oxygen species.
  • Clinical Data: Clinical study on vaginal yarrow cream in vulvovaginal candidiasis.
  1. Cancer
  • Animal Data: In vitro studies suggest apoptotic and antitumor activity against various human cancer cell lines.
  • Clinical Data: Inconclusive data, with one study showing potential healing rates in oral mucositis.
  1. Cardiovascular
  • Animal Data: Effects on vascular smooth muscle cells, hypotensive effects, and diuretic effects demonstrated in rats.
  • Clinical Data: Limited data; related plant Achillea wilhelmsii shows antihypertensive and lipid-modifying effects.
  1. Renal Effects
  • Animal Data: Yarrow extracts show diuretic effects in rats, protect against induced nephrolithiasis, and exhibit antioxidant effects in the kidney.
  • Clinical Data: Reductions in plasma nitrite and nitrate content observed in a clinical trial involving patients with chronic kidney disease.
  1. Other Uses
  • Traditional uses as a hemostatic agent and for cerebral and coronary thrombosis lack clinical validation.
  • Anxiolytic effects in mice.
  • Dermatological applications, wound healing, and relaxant effects on smooth muscle tissue studied in animals.

Dosing


Traditionally, yarrow herb at 4.5 g/day has been used for various conditions. However, there are no quality clinical studies to validate this dosing.

Pregnancy / Lactation


Avoid use, as documented adverse effects exist, and thujone present in small amounts is an abortifacient.

Interactions


No well-documented interactions. Interactions may occur with diuretic medicines.

Adverse Reactions


Contact dermatitis is the most commonly reported adverse reaction, and its use is contraindicated in known allergies to any members of the Aster family. Data for reported contraindications in epilepsy are lacking. One case report exists documenting anticholinergic adverse effects associated with the consumption of 5 cups of yarrow tea per day for one week.

Toxicology


Yarrow is not generally considered toxic; however, an antispermatogenic effect has been reported. Safety data are insufficient to support the safe use of the herb in cosmetic products. Thujone-free preparations are recommended due to its abortifacient potential. Cosmetic products containing A. millefolium are deemed safe according to the Cosmetic Ingredient Review Expert Panel in 2016.