Insulin delivery by injection in children and adolescents with diabetes.

Type 1 diabetes is treated with insulin, which has traditionally been delivered by vial and syringe. However, for many patients, dosing inaccuracy, pain, anxiety, inconvenience, and social acceptability present barriers to this method of administration (1-5). This has contributed to the increased popularity of alternative insulin delivery systems, including pen delivery devices (4, 6). Evidence suggests that discreet devices, such as insulin pens, facilitate adherence to intensive insulin therapy regimens, help improve lifestyle flexibility, and reduce injection pain compared with the conventional syringe-based regimens, as shown in studies in adults and adolescents (7). In addition, compared with the vial and syringe method of insulin administration, pens may provide more accurate dosing - which is particularly important in children - thereby improving short-term blood glucose control and potentially improving long-term outcomes (5, 8). Children, in particular, may benefit from insulin pens that are simple to use as adherence issues may be more evident in this patient group (9). Pens for insulin delivery in children with type 1 diabetes have been used for a long time in Europe, and have recently gained in popularity in many other places around the world (4, 10). Furthermore, the conventional vial and syringe method of insulin delivery is beginning to be considered as obsolete (11). Moreover, there is a continued drive to improve insulin pen technology, to refine and enhance the functionality and usability of these pens. However, despite recent advances in pen design and function, the selection of pens available especially for children is limited.