Certified Diabetes Educator Practice Exam 2025 - Free Practice Questions and Study Resource.

DPP-4 inhibitors lower blood sugar levels primarily by inhibiting glucagon production, which is crucial in glucose regulation. Glucagon is a hormone produced by the pancreas that has the opposite effect of insulin; it stimulates the liver to release glucose into the bloodstream. By reducing glucagon levels, DPP-4 inhibitors help to lower the amount of glucose released from the liver, thus contributing to more stable blood sugar levels.

In addition to inhibiting glucagon, DPP-4 inhibitors also enhance the action of incretin hormones, which are responsible for stimulating insulin secretion in response to meals. This dual action results in a more effective management of postprandial (after eating) blood sugar levels, as well as overall blood glucose control throughout the day.

The other options do not accurately describe the mechanism of action for DPP-4 inhibitors. Increasing stomach acidity, enhancing fat absorption, and speeding up carbohydrate digestion are not primary functions of these medications and do not directly relate to the management of blood glucose levels in the way that inhibiting glucagon does.