Answered 9/9/2014 by Samuel Grossman, BS Pharm, Pharm.D, CDE
Diabetes is a progressive disease which means that when glucose levels are not optimally controlled the cells that produce insulin are not going to be able to meet the demand as time goes by. Oral medications either work with existing insulin, increase the release of more insulin from the pancreas, reduce the absorption of glucose from the kidneys or stop the liver from releasing sugar. With the progression of diabetes, the ability of oral medications to increase release of insulin from the pancreas goes down. In addition, other methods may not be enough to reduce blood sugar effectively. Insulin that is injected from outside of the body has the ability to meet the demands of each individual. If one dose is not sufficient the dose of insulin can be titrated to control blood sugar.