Achillea Millefolium, Yarrow

Common names and History

Yarrow, Milfoil, Old man’s pepper, Soldier’s woundwort, Knight’s milfoil, Thousand weed, Nose bleed, Carpenter’s weed, Bloodwort, Staunchweed, Sanguinary, Devil’s nettle, Devil’s plaything, Devil’s mustard, Bad man’s plaything, Yarroway.

Yarrow was valued as a vulnerary especially for wound healing in the medieval times as it is suggested by its various names such as ‘soldier’s woundwort’; ‘ knights milfoil’; ‘staunchweed’, ‘carpenter’s weed’ etc.. Additionally, yarrow was used in divination of spells, especially to the Evil One, again this is illustrated in its common names such as ‘devil’s plaything’, ‘devil’s nettle’, ‘bad man’s plaything’ etc.
Its use as snuff are also depicted in ‘old man’s pepper’ (this is due to the pungency of its foliage) and as a remedy for nosebleeds either for staunching or provoking a bleed, which could be used as a relief for headaches and migraines.

However it is believed that its generic name of Achillea comes from the Greek legend of Achilles who saved the lives of his warriors during the Trojan War by healing their wounds with yarrow leaves. The Old English Herbarium describes this the following way: These plants which one calls ‘millefolium’ and in our language ‘yarrow’, it is said that Achilles the ealdorman is supposed to have found them, with this same plant he healed those who had been struck and wounded by iron, also for that reason it is called by some people ‘achylleos’; with that plant it is also said that he is supposed to have healed a certain man, whose name was Telephon (Pollington, 2003: 327-329 §90).
It was already known to the Romans as Herba Militaris . Its Anglo-Saxon name is Gearwe.

Medicinal uses

Diaphoretic, antipyretic, hypotensive, peripheral vasodilator, astringent, haemostatic, diuretic, urinary antiseptic, anti-inflammatory, spasmolytic, aromatic bitter, digestive stimulant, emmenagogue, restorative and regulator for menstrual system. The essential oil is anti-inflammatory, anti-allergenic and antispasmodic (please see Glossary).

Benefits

Fevers, common cold, essential hypertension, digestive complaints, loss of appetite, amenorrhoea, dysentery, diarrhoea. Specifically indicated in thrombotic conditions with hypertension, including cerebral and coronary thromboses. Used topically for slow-healing wounds and skin inflammations.

Achillea is a valuable diaphoretic herb and is the central ingredient in any fever-management programme. It prevents the body temperature from rising too high but has a minimal suppressant effect on the course of the fever. 

The flowers are rich in chemicals that are converted by steam distillation into anti-allergenic compounds, of use in the treatment of allergic catarrhal problems such as hayfever. The dark blue essential oil, azulene, is generally used as an anti-inflammatory, or in chest rubs for colds and influenza.

Achillea lowers high blood pressure by dilating the peripheral vessels, and it also tones the blood vessels. It is considered to be a specific in thrombotic conditions associated with high blood pressure. Used externally, its astringent properties will aid in the healing of wounds, and it has been used to treat haemorrhoids and varicose veins. The leaves encourage blood clotting, so can be used fresh for nosebleeds. However, inserting a leaf in the nostril may also start a nosebleed. Achillea has also been used in the treatment of heavy and painful periods, and the presence of steroidal constituents may help to explain this activity.

The spasmolytic action of Achillea is attributed to its flavonoid content. The flavonoids help to dilate the peripheral arteries and are also believed to help clear blood clots. The flavonoid apigenin is anti-inflammatory, spasmolytic and anti-platelet; salicylic acid is anti-inflammatory, as is azulene, which also stimulates the formation of granulation tissue in wound healing. The volatile oil eugenol has local anaesthetic activity, while cineol has antiseptic and expectorant properties. The alkaloid achilleine has been shown to be haemostatic, reducing clotting time without toxic side-effects. It has also been reported to lower blood pressure. Cyanidin is anti-inflammatory and also influences the vagus nerve, slowing the heart rate. The bitter action of Achillea stimulates the digestion and the tannins have an astringent effect both internally and externally. The diuretic, expectorant and digestive stimulant action can be explained by the volatile oil content of the plant. The cyanogenic glycosides and isovalerianic acid have a sedative action and asparagin is a potent diuretic. Central nervous system depressant activity has been documented for the volatile oil, and antimicrobial properties are ascribed to the sesquiterpene lactone fraction. Moderate antibacterial activity has been documented for an ethanolic extract of Achillea against Staphylococcus aureus, Bacillus subtillus, Mycobacterium smegmatis, Escherichia coli, Shigella sonnei and Shigella flexnii.

Warnings

Yarrow is usually considered safe to use with little or no side-effects, however notes of caution have been found.
They have been reports that it is the sesquiterpene lactones that are responsible for the allergic reaction (especially allergic contact dermatitis) caused by yarrow (Bradley, 1992; Mills, 1994; Barnes et al., 2002; Bone, 2003; Williamson, 2003).
It may cause photo-sensitivity Bradley, 1992; Mills, 1994; Barnes et al., 2002).
Barnes et al. (2002) mention that it may interfere with existent anti-coagulant and hypertensive treatments and that it may have a sedative and diuretic effect.
It should be avoided during pregnancy (due to the high amount of volatile oils), it is a reputed arborificient and emmenogogue, and therefore it may affect the menstrual cycle and should also be avoided during lactation (Barnes et al., 2002).