Comparison between insulin delivery methods: subcutaneous, inhaled, oral, and buccal

Diabetes mellitus is a complex and chronic metabolic disorder characterized by hyperglycemia. Part of the treatment for this condition is the administration of insulin, a protein that directly influences blood glucose levels. It is traditionally administered parenterally; however, new alternative ways for its application seek greater efficiency and less invasiveness. The objective of this article is to compare the different methods of insulin administration, taking into account new technologies. This review article provides an overview of diabetes and insulin, highlights the advantages and disadvantages of insulin delivery methods (subcutaneous, inhaled, oral, and buccal), and shows the new technologies that include biotechnological applications.