A. Because diabetes can change and progress over time, especially if the disease is poorly controlled (i.e., blood sugar levels are chronically high), oral diabetes medications may stop working or lose their effectiveness after a few months or a few years. If diabetes progressively gets worse, the pancreas may become less able to produce insulin and your medication needs may change. That’s why it’s important to check your blood sugar levels and see your doctor on a regular basis. Your diabetes health care provider should monitor the effectiveness of your medication and assess the need to combine with other oral diabetes medications, insulin, or both.