Janumet XR CP Tablet is a combination oral antidiabetic medication containing Sitagliptin 100mg and Metformin 1000mg, indicated for the management of type 2 diabetes mellitus. Sitagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor, enhances the incretin system by increasing levels of active incretin hormones, which regulate glucose homeostasis by increasing insulin synthesis and release from pancreatic beta cells and decreasing glucagon secretion from alpha cells. Metformin, a biguanide, primarily acts by decreasing hepatic glucose production, improving insulin sensitivity, and enhancing peripheral glucose uptake and utilization. The extended-release formulation of Janumet XR CP allows for once-daily dosing, improving patient compliance and maintaining stable plasma drug concentrations. This combination therapy is particularly beneficial for patients inadequately controlled on metformin alone or those requiring dual therapy to achieve glycemic targets. Janumet XR CP should be used alongside diet and exercise to optimize glycemic control. Common adverse effects may include gastrointestinal disturbances such as nausea, diarrhea, and abdominal discomfort, with a low risk of hypoglycemia when used as monotherapy. Caution is advised in patients with renal impairment, hepatic dysfunction, or conditions predisposing to lactic acidosis. Regular monitoring of renal function and glycemic parameters is recommended during treatment.