Numerous traditionally used plants exhibit pharmacological properties with great potential for therapeutic applications in the treatment of central nervous system disorders, such as anxiety dis-orders. Achillea millefolium, known as yarrow (“mil folhas”), is a perennial herb that has been used for hundreds of years in folk medicine in sev-eral countries. In Germany and Italy, it is used for the treatment of gastrointestinal disturbances. In Britain and North America, it is used to treat bleeding. In Brazil, its main indication is for the treatment of pain, wounds, inﬂammation, and gastrointestinal complaints, although plant infusion or the decoction of the aerial parts of the plant is indicated for “calmness”. This latter indication is also seen in Mexico.