Diabetes mellitus results from an inadequate production of insulin from the pancreas. The primary treatment is replacement by insulin injections. The body’s response to the injections needs to be regularly monitored using an at-home glucometer or continuous glucose monitoring system. Insulin must be stored and reconstituted carefully to ensure dosing is accurate. Giving subcutaneous injections of insulin can seem daunting at first, but by following the directions in this handout, it will quickly become second nature to both you and your pet.