What is the mechanism of action of alpha-glucosidase inhibitors?

• A. Direct stimulation of insulin release
• B. Delayed absorption of carbohydrates
• C. Increased hepatic glucose production
• D. Renal glucose excretion

Answer: (B)

Alpha-glucosidase inhibitors work by blocking the intestinal brush-border enzymes that break down complex carbohydrates into absorbable glucose. By inhibiting these enzymes, carbohydrate digestion is slowed, delaying glucose absorption and blunting the post-meal rise in blood glucose. This effect is localized to the gut and does not stimulate insulin release, increase hepatic glucose production, or cause renal glucose excretion. GI side effects from undigested carbohydrates reaching the colon are common, such as gas and diarrhea.