Metformin + Glimepiride is a potent, synergistic, oral fixed-dose combination (FDC) antidiabetic medication used for the management of type 2 diabetes mellitus (T2DM) in patients inadequately controlled on either monotherapy. Metformin, a biguanide, primarily reduces hepatic glucose production and improves insulin sensitivity. Glimepiride, a sulfonylurea (third-generation), stimulates insulin secretion from pancreatic beta cells. This combination addresses both insulin resistance and insulin deficiency, offering a comprehensive approach to glycemic control. It is a cornerstone therapy in the Indian diabetes management algorithm, especially for patients with HbA1c > 8.5%.
Adult: Individualized. Common starting strength: Metformin 500 mg + Glimepiride 1 mg or 2 mg once or twice daily with meals. Maximum daily dose: Metformin 2000 mg + Glimepiride 4 mg (or as per specific brand limits). Dose titration should be at 1-2 week intervals.
Note: Take with or immediately after main meals to reduce gastrointestinal side effects (from metformin) and minimize risk of hypoglycemia. Swallow whole with a glass of water. Do not crush or chew. Maintain regular meal patterns.
The combination exerts a dual mechanism: Metformin decreases hepatic gluconeogenesis and glycogenolysis, increases peripheral glucose uptake and utilization (improving insulin sensitivity), and delays intestinal absorption of glucose. Glimepiride binds to sulfonylurea receptors (SUR1) on pancreatic beta-cell membranes, leading to closure of ATP-sensitive potassium channels, membrane depolarization, calcium influx, and subsequent exocytosis of insulin granules.
Pregnancy: Pregnancy Category C/D (varies). Insulin is the preferred treatment for glycemic control in pregnant women with diabetes. This combination is not recommended. Metformin may be used in some cases of PCOS/gestational diabetes under strict supervision, but glimepiride (sulfonylurea) can cross placenta and cause neonatal hypoglycemia.
Driving: Caution advised. Hypoglycemia can impair concentration and reaction time. Patients should be aware of hypoglycemia symptoms and check blood glucose before driving.
| Other Antidiabetics (Insulin, DPP-4 inhibitors, etc.) | Increased risk of hypoglycemia | Major |
| Beta-blockers (e.g., Propranolol) | Masked hypoglycemic symptoms (tachycardia); may potentiate hypoglycemia | Moderate |
| Alcohol | Increased risk of lactic acidosis (metformin) and potentiation of hypoglycemia (glimepiride); disulfiram-like reaction | Major |
| Corticosteroids (e.g., Prednisolone) | Decreased hypoglycemic effect; loss of glycemic control | Moderate |
| Diuretics (Thiazides, Loop diuretics) | May cause hyperglycemia; risk of lactic acidosis with metformin if dehydration occurs | Moderate |
| Warfarin | Glimepiride may potentiate warfarin effect (increased INR) | Moderate |
| CYP2C9 Inhibitors (e.g., Fluconazole, Amiodarone) | Increased glimepiride plasma levels → hypoglycemia risk | Moderate |
| CYP2C9 Inducers (e.g., Rifampicin) | Decreased glimepiride plasma levels → hyperglycemia | Moderate |
| Cationic Drugs (e.g., Cimetidine, Ranitidine) | Competition for renal tubular secretion → increased metformin levels | Moderate |
| Iodinated Contrast Media | Risk of lactic acidosis and acute renal failure. Metformin must be withheld before and after procedure. | Major |
Same composition (Metformin + Glimepiride), different brands: