A type 2 diabetic patient is prescribed acarbose as add-on therapy. Which mechanism best describes its glucose-lowering action?

• A Inhibits sodium-glucose cotransporter 2 in the proximal tubule
• B Inhibits alpha-glucosidase in the small intestinal brush border ✓
• C Stimulates insulin release by closing K-ATP channels on beta cells
• D Activates PPAR-gamma to improve peripheral insulin sensitivity

Explanation

Acarbose competitively inhibits alpha-glucosidase enzymes (maltase, sucrase, glucoamylase) in the small intestinal brush border, delaying carbohydrate digestion and glucose absorption, thereby reducing postprandial hyperglycemia. It does not affect insulin secretion, insulin sensitivity, or renal glucose handling.

Reference: Katzung Basic and Clinical Pharmacology, 15th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.