Metformin: Uses, Mechanism and Medical Significance

Introduction: Metformin is an oral antidiabetic medicine widely used in the management of type 2 diabetes mellitus. It helps improve glucose regulation, particularly by reducing hepatic glucose production.

Key pointers

  • Drug category: Biguanide antidiabetic medicine.

  • Primary use: Management of type 2 diabetes.

  • Mechanism: Reduces glucose production by the liver and improves insulin sensitivity.

  • Insulin secretion: Unlike sulfonylureas, metformin does not primarily work by directly stimulating pancreatic insulin release.

  • Blood glucose: Helps lower blood glucose levels and can improve long-term glycaemic control.

  • Body weight: Is generally weight-neutral or may produce modest weight loss.

  • Hypoglycaemia: Has a relatively low risk when used alone, although risk can increase with certain combinations.

  • Adverse effects: Gastrointestinal symptoms such as nausea, diarrhoea and abdominal discomfort are common.

  • Rare serious risk: Lactic acidosis, particularly in patients with major predisposing conditions.

  • Kidney function: Renal function must be considered when prescribing because the drug is cleared primarily through the kidneys.

  • Additional consideration: Long-term use may be associated with vitamin B12 deficiency in some patients.

UPSC focus: Metformin belongs to the biguanide class and is commonly used in type 2 diabetes. It is not insulin and does not directly replace the body's insulin.