What is the generic name for Januvia?

The generic name for Januvia is sitagliptin. This medication is classified as a dipeptidyl peptidase-4 (DPP-4) inhibitor and is primarily used in the treatment of type 2 diabetes. It works by increasing the levels of incretin hormones, which help regulate blood sugar levels by increasing insulin release in response to meals and decreasing glucagon secretion, subsequently lowering glucose production in the liver.

In this context, the other choices represent different diabetes medications that have distinct mechanisms of action. Metformin is a biguanide that decreases hepatic glucose production and improves insulin sensitivity. Glipizide is a sulfonylurea that stimulates insulin secretion from the pancreas. Pioglitazone is a thiazolidinedione that enhances insulin sensitivity and also has effects on glucose metabolism. Each of these drugs plays a specific role in diabetes management but is not the generic name for Januvia. Thus, sitagliptin is recognized as the correct answer for the generic name of Januvia.