Metformin

Also known as French lilac, the herb Galega officinalis was used as a traditional medicine in medieval Europe, apparently helpful against worms, epilepsy and fever. In 1772 it was used to treat thirst and frequent urination, both symptoms of diabetes (Bailey, 2017). Later found to be guanidine-rich, G. officinalis was shown in 1918 to lower blood glucose concentrations; the derivative metformin (dimethylbiguanide) was synthesised in 1922; and in 1957 the French physician Jean Sterne first reported the use of metformin to treat diabetes (Bailey, 2017).

Following improved morbidity and mortality in type 2 diabetes (T2D) demonstrated in the United Kingdom Prospective Diabetes Study, metformin has been the first-line recommended oral treatment for T2D diabetes by the American Diabetes Association and the European Association for the Study of Diabetes since 2009 (Thomas and Gregg, 2017). Metformin reduces the production of liver glycogen without raising insulin concentrations; inhibits glucose absorption in the intestinal tract; and increases the uptake and utilisation of glucose in the peripheral tissues, all of which increase insulin sensitivity (Liu et al, 2023).