Metformin is one of the most commonly prescribed drugs for management of Type 2 diabetes mellitus. It has been in use for almost five decades. Now, pharmacological properties of this agent are being exapted for use in a number of other indications. New facets of its personality are coming up, generating more interest of the scientific community in this "middle-aged" molecule. This article explores the role of metformin in cardioprotection and its hepatoprotective properties. Nephroprotective, protection against excess body fat and gonadoprotective actions, properties have also been discussed. Additionally, this manuscript briefly reviews the thyroid stimulating hormone (TSH)-lowering properties in diabetic and non-diabetic patients, besides reviewing its actions on different types of cancers. Some of these actions may become approved indications for use of metformin following generation of new evidence. Metformin still has many unexplored dimensions that deserve further exploration.
Keywords: Biguanides; cancer; cardioprotection; diabetes; gonad; hepatoprotection; oral hypoglycemic drugs; renoprotection; thyroid.