How does Metformin primarily prevent high blood glucose levels?

Metformin primarily prevents high blood glucose levels by decreasing glucose production and release from the liver. The liver plays a crucial role in glucose metabolism, and in individuals with insulin resistance or type 2 diabetes, it can overproduce glucose, especially during fasting states. Metformin works by reducing hepatic gluconeogenesis, which is the process of converting non-carbohydrate sources into glucose in the liver. This reduction in glucose output helps lower blood glucose levels, especially after meals and during periods of fasting.

In contrast, increasing insulin production or stimulating pancreatic beta cells would focus on enhancing insulin secretion, which is not the primary mechanism of action for metformin. Blocking glucose absorption in the intestine is also not a function of metformin; that action is typical of other medications like alpha-glucosidase inhibitors. Therefore, the distinct mechanism of action of metformin in reducing hepatic glucose production is what makes this answer correct.