Which mechanism describes the action of alpha-glucosidase inhibitors?

• A. Delay intestinal carbohydrate absorption by inhibiting alpha-glucosidase enzymes.
• B. Stimulate insulin secretion from the pancreas.
• C. Increase hepatic glucose production.
• D. Block glucose uptake in the kidney.

Answer: (A)

Alpha-glucosidase inhibitors slow the intestinal digestion of carbohydrates by blocking the brush-border alpha-glucosidase enzymes in the small intestine. By inhibiting these enzymes, the breakdown of disaccharides and oligosaccharides into glucose is delayed, leading to a slower, smaller postprandial rise in blood glucose. This is why the mechanism described as delaying intestinal carbohydrate absorption by inhibiting alpha-glucosidase enzymes is correct. They do not stimulate insulin secretion, do not raise hepatic glucose production, and do not block renal glucose reabsorption, so those options don’t fit.