indication

For the reatment of type II diabetes mellitus.

pharmacology

Used to treat diabetes, phenformin is a biguanide (contains 2 guanidino groups) hypoglycemic agent with actions and uses similar to those of metformin (Glucophage). Both drugs work by (1) decreasing the absorption of glucose by the intestines, (2) decreasing the production of glucose in the liver, and by (3) increasing the body's ability to use insulin more effectively. More specifically, phenformin improves glycemic control by improving insulin sensitivity. Phenformin is generally considered to be associated with an unacceptably high incidence of actic acidosis. In general biguanides should be used only in stable type II diabetics who are free of liver, kidney and cardiovascular problems and who cannot be controlled with diet.

mechanism of action

Phenformin binds to the AMP-activated protein kinase (AMPK). AMPK is an ultra-sensitive cellular energy sensor that monitors energy consumption and down-regulates ATP-consuming processes when activated. The biguanide phenformin has been shown to independently decrease ion transport processes, influence cellular metabolism and activate AMPK. Phenformin's hypoglycemic activity is related the effect it has in activating AMPK and fooling insulin sensitive cells into thinking that insulin levels are low and causing the body to use glucose as if in a state of low caloric consumption. This drug also seems to inhibit several varients of ATP-sensitive potassium channels (namely the receptor subtype Kir6.1).