Flowers of Galega officinalis, ( Goat's Rue, French Lilac ). A native of C and S Europe to Turkey and Pakistan, G. officinalis has been used to treat diabetes since the Middle Ages. The active principle was sought in the early 20th century, which led to research on guanidine derivatives. The current most widely used treatment for Type 2 diabetes is Metformin, a biguanidine molecule which reduces the level of glucose in the blood by action on the liver.G. officinalis is now regarded as poisonous, but is widely available as a garden plant. It is a vigorous clump-forming perennial which self-seeds. It occurs sporadically in the wild far beyond its natural range, due to escaping from gardens, and as a result of earlier use of the plant in agriculture as a green manure and forage crop. It is listed as a Federal Noxious Weed in the USA