Galega officinalis

Galega officinalis (also known as Goat's Rue, French Lilac, Italian Fitch or Professor-weed) is a plant from the Galega genus of the Faboideae. Its name derives from gale (milk) and ega (to bring on), as Galega has been used as a galactologue in small domestic animals (hence the name "Goat's rue"). Galega bicolor is a synonym. It is a hardy perennial that blooms in the summer months.

Other Galega species are Galega orientalis.

Galega is used as a food plant by the larva of Coleophora vicinella, a species of moth.

Medical use
Galega officinalis has been known since the Middle Ages for relieving the symptoms of diabetes mellitus. Upon analysis, it turned out to contain guanidine, a substance that decreases blood sugar by decreasing insulin resistance.

Chemical derivatives from the biguanide class of medication include metformin (Glucophage, commonly prescribed for diabetics) and the older, withdrawn agent phenformin.