Found throughout Europe and now America, Yarrow (Achillea millefolium) has for many years been used by herbalists for a variety of complaints. Yarrow contains lactones, flavonoids, tannins, resins, coumarins, saponins, sterols, fatty acids and sugars. The best studied, and possibly the most active constituents are the volatile oils like azulene, pinenes, borneols and others. Yarrow has been reported to have anti-inflammatory, hypotensive, astringent, antibacterial and choleretic (bile stimulating) activities. King's American Dispensary lists yarrow as one of the best agents for relief of menorrhagia (profuse menstrual bleeding) because of its ability to relax the uterine wall. Look for yarrow in teas, tinctures and powders.