Structure
Metformin is a biguanide derivative with two guanidine groups attached to a dimethylamine backbone.
Chemical Formula: C₄H₁₁N₅

Mode of Action
AMP-Activated Protein Kinase (AMPK) Activation: Enhances insulin sensitivity and reduces hepatic gluconeogenesis.
Intestinal Glucose Uptake Inhibition: Decreases glucose absorption from the gastrointestinal tract.
Decreased Lipolysis: Reduces free fatty acid levels, improving insulin sensitivity.
Uses
Type 2 Diabetes Mellitus: First-line therapy for improving glycemic control.
Polycystic Ovary Syndrome (PCOS): Enhances insulin sensitivity and regulates menstrual cycles.
Prevention of Type 2 Diabetes: In individuals with impaired glucose tolerance.