What is the mechanism of action of metformin?

Metformin primarily works by reducing hepatic glucose production. This means that it decreases the amount of glucose that the liver releases into the bloodstream. By doing so, metformin helps lower blood sugar levels, particularly in individuals with type 2 diabetes. This action plays a crucial role in controlling hyperglycemia and is particularly beneficial for reducing fasting blood glucose levels.

In addition to this principal mechanism, metformin also has a secondary effect of promoting peripheral insulin sensitivity, which enhances the uptake of glucose by muscle and fat cells. However, the predominant and most distinctive action of metformin is its effect on the liver's glucose output. This makes it unique among antidiabetic medications, which often focus more directly on enhancing insulin secretion or absorption pathways. Understanding this mechanism is fundamental for recognizing how metformin effectively manages blood sugar levels in diabetic patients.