Which drugs are sulfonylureas?

• A. Metformin and pioglitazone
• B. Glipizide and glimepiride
• C. Exenatide and liraglutide
• D. Acarbose and miglitol

Answer: (B)

Sulfonylureas work by stimulating the pancreas to release more insulin. They do this by blocking ATP-sensitive potassium channels on pancreatic beta cells, which causes the cell to depolarize and secrete insulin. Glipizide and glimepiride are classic examples of this class, so they are sulfonylureas. The other drug pairs belong to different mechanisms: metformin lowers hepatic glucose production, pioglitazone is a thiazolidinedione that improves insulin sensitivity, exenatide and liraglutide are GLP-1 receptor agonists, and acarbose and miglitol inhibit intestinal carbohydrate absorption.