Chlorpropamide is used along with a proper diet and exercise program to control high blood sugar in people with type 2 diabetes (non-insulin-dependent diabetes). Controlling high blood sugar helps prevent kidney damage, blindness, nerve problems, loss of limbs, and sexual function problems. Proper control of diabetes may also lessen your risk of a heart attack or stroke. Chlorpropamide belongs to the class of drugs known as sulfonylureas. It works by stimulating the release of your body's natural insulin, thereby lowering your blood sugar.