Biguanides
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Overview
Biguanides are oral antidiabetic agents that lower blood glucose primarily by reducing hepatic glucose production. Metformin is the only biguanide in clinical use and is the first-line pharmacologic treatment for type 2 diabetes mellitus.
How do biguanides work?
Metformin activates AMP-activated protein kinase (AMPK), which inhibits hepatic gluconeogenesis and glycogenolysis, the primary driver of fasting hyperglycemia in type 2 diabetes. It also improves peripheral insulin sensitivity in muscle and adipose tissue, slows intestinal glucose absorption, and does not stimulate insulin secretion, thus carrying minimal risk of hypoglycemia.
Drugs in this class
- Metformin (Glucophage, Glumetza, Fortamet)