A glorious past, dynamic present and a promising future: Insulin at 100.

It has been 100 years since insulin was discovered. Insulin therapy remains the cornerstone for the management of diabetes. Advances in human physiology, pathology, molecular biology, biotechnology, biomedical engineering and devices have added tremendously to the journey of one of the greatest discoveries of modern medicine. Epidemiology of diabetes has gone through a major shift in a century; many oral drugs have been introduced for the management of type 2 diabetes; glucose monitoring has also gone through a sea change with the availability of novel parameters like continuous glucose monitoring, as has insulin delivery, with the availability of insulin pumps and the artificial pancreas. In this article, we look into historical facts, challenges, limitations and future developments of insulin therapy.