What is the mechanism of action of acarbose and when is it used?

• A. Alpha-glucosidase inhibitor; delays carbohydrate absorption; used for postprandial hyperglycemia
• B. Inhibits DPP-4 enzyme; used for fasting hyperglycemia
• C. Increases insulin sensitivity via PPAR-gamma; used for chronic management
• D. Delays hepatic glucose production; used for basal hyperglycemia

Answer: (A)

Acarbose works by blocking alpha-glucosidase enzymes in the lining of the small intestine. By slowing the breakdown of complex carbohydrates into glucose, it reduces how quickly glucose is absorbed after a meal, leading to a smaller rise in blood sugar postprandially. This makes it useful for addressing postprandial hyperglycemia in type 2 diabetes, and it can be used alone or with other antidiabetic agents to help control meal-driven glucose spikes. It’s not intended to lower fasting glucose. Other options describe different drug classes (for example, DPP-4 inhibitors affect incretin hormones, PPAR-γ agonists improve insulin sensitivity, and metformin reduces hepatic glucose production), so their actions and typical use differ from acarbose.