Metformin: A Comprehensive Clinical and Pharmacological Review of Its Spectrum, Efficacy, Resistance, and Safety Profile

Metformin is an oral antihyperglycemic agent belonging to the biguanide class and is widely accepted as the first-line pharmacological therapy for type 2 diabetes mellitus. It exerts its primary action by reducing hepatic glucose production and improving peripheral insulin sensitivity without causing significant hypoglycemia. Over several decades of clinical use, metformin has demonstrated an excellent safety profile along with additional benefits such as weight neutrality, cardiovascular protection, and potential anticancer effects. This article provides a comprehensive review of the history, chemistry, mechanism of action, pharmacokinetics, pharmacodynamics, therapeutic uses, adverse effects, contraindications, drug interactions, and future perspectives of metformin