Both yarrow herb, consisting of the dried, flowering shoot tips, and yarrow flowers, consisting of the dried inflorescences of the yarrow, are used pharmaceutically for medicinal purposes. The drug is an ingredient in numerous tea blends and ready-to-use medicines.

In laboratory studies, yarrow has shown a variety of effects, such as anti-inflammatory, antispasmodic, antimicrobial and antifungal properties, and it also promotes the flow of bile.

Yarrow has an aromatic, bitter flavour, which is why, like chamomile flowers, it is used to treat loss of appetite and digestive disorders, such as mild cramp-like complaints in the gastrointestinal tract. Traditional medicine has also documented its use for mild cramps associated with menstruation and for superficial wounds.

In addition to the essential oil (the composition varies depending on the yarrow variety, important components are β-pinene, sabinene, 1,8-cineole, camphor, β-caryophyllene, germacrene D), sesquiterpene lactones (achillicin), germacranolides, polyacetylenes, flavonoids and phenolcarboxylic acids. Azulenes (substances that colour the distilled essential oil blue) are also not found in all varieties of yarrow.

Care should be taken when using them, as representatives of some yarrow species can trigger allergies.

Yarrow or common yarrow (Achillea millefolium L. in the broader sense) is a collective species in which species with different chromosome sets, different appearances and different constituents are grouped together. The perennial herb from the composite family grows up to 80 cm high.

The common yarrow has typically two to three-pinnate leaves with several pairs of leaflets.

The individual flower heads with their bright white to pink-coloured ray florets are also grouped together in an umbel to make them even more attractive to pollinators. Flowering time is from July to October.