Which diabetes medication primarily works by increasing insulin sensitivity?

The medication that primarily works by increasing insulin sensitivity is pioglitazone. This class of medication, known as thiazolidinediones, focuses on enhancing the body's responsiveness to insulin, particularly in muscle and adipose tissue. By improving insulin sensitivity, pioglitazone helps lower blood glucose levels in individuals with type 2 diabetes.

Metformin, while it does have a role in increasing insulin sensitivity, primarily works by reducing hepatic glucose production and improving glucose uptake in peripheral tissues rather than focusing solely on enhancing insulin sensitivity. Glyburide is a sulfonylurea that functions by stimulating insulin secretion from the pancreas, and sitagliptin is a DPP-4 inhibitor that works by increasing incretin levels to enhance insulin secretion and decrease glucagon levels in a glucose-dependent manner. Thus, although they contribute to glucose control in different ways, pioglitazone is explicitly recognized for its primary action of improving insulin sensitivity.