Goat's Rue is a member of the Pea family and not, as the name might suggest, a true Rue, (Rutaceae or Citrus family). Nothing is known about the use of this plant in the classical period, but in the Middle Ages it was thought powerful enough to ward off the Plague. Culpepper recommends a footpath for those tired from walking and also says that it was used for cheese-making instead of rennet. The name 'Galega' roughly translates as 'discharge milk', a reference to its galactagogue properties. Apparently, it increases milk production by as much as 30%. However, it proved too toxic to animals and the practice of adding it to the fodder was thus abandoned. In the US it is considered a noxious weed.
In Medieval times the herb was mainly used to dispel worms, cure the bites of venomous beasts and to improve digestion. A newly discovered property is the herb's ability to reduce blood sugar levels, which is useful in the treatment of diabetes. The pharmaceutical drug Metformin, which is one of the most commonly prescribed drugs for diabetes, is based on guanidine, a compound found in Goat's Rue.
Used in healing rituals, to ward off 'the evil spirits of disease'. It can also be used to tune into and attract abundance.