A fixed-dose combination (FDC) oral antidiabetic medication containing Sitagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor, and Metformin, a biguanide. This combination provides complementary mechanisms of action to improve glycemic control in adults with type 2 diabetes mellitus (T2DM) by increasing incretin levels (GLP-1 and GIP) to stimulate glucose-dependent insulin release and suppress glucagon secretion, while simultaneously decreasing hepatic glucose production and improving insulin sensitivity. It is indicated when treatment with metformin alone does not provide adequate glycemic control.
Adult: One tablet twice daily, with meals (typically breakfast and dinner). The maximum recommended daily dose is Sitagliptin 100mg + Metformin 2000mg.
Note: Swallow whole with a glass of water. Must be taken with or immediately after meals to reduce gastrointestinal upset from metformin. Do not crush or chew.
The combination exerts a synergistic glucose-lowering effect through two distinct pathways. Sitagliptin inhibits the enzyme DPP-4, thereby increasing the concentrations of active incretin hormones (GLP-1 and GIP). This enhances glucose-dependent insulin secretion from pancreatic beta cells and suppresses glucagon secretion from alpha cells. Metformin decreases hepatic gluconeogenesis and glycogenolysis, improves peripheral glucose uptake and utilization, and may have a mild anorectic effect.
Pregnancy: Pregnancy Category B (US FDA). Not recommended during pregnancy. Insulin is the preferred drug for glycemic control in pregnant women with diabetes. Limited human data.
Driving: Usually no effect. However, patients should be cautioned about the risk of hypoglycemia (especially when combined with other agents) or dizziness, which may impair ability to drive or operate machinery.
| Cimetidine | Increases metformin plasma concentration by competing for renal tubular secretion. | Moderate |
| Carbonic Anhydrase Inhibitors (e.g., Topiramate, Acetazolamide) | May increase risk of lactic acidosis. | Major |
| Iodinated Contrast Media | Risk of acute renal failure and lactic acidosis. Metformin should be withheld before and after procedure. | Major |
| Alcohol | Potentiates metformin's effect on lactate metabolism; increases risk of lactic acidosis and hypoglycemia. | Major |
| Sulfonylureas (e.g., Glimepiride) or Insulin | Increased risk of hypoglycemia. May require dose reduction of sulfonylurea/insulin. | Moderate |
| Digoxin | Metformin may increase digoxin concentration. | Moderate |
| Diuretics (especially loop diuretics) | May affect renal function and increase metformin levels/risk. | Moderate |
| Corticosteroids | May lead to loss of glycemic control, requiring dose adjustment. | Moderate |
Same composition (Sitagliptin (50mg) + Metformin (500mg)), different brands: