The original insulin delivery system, syringes are still an option for people with diabetes. Insulin is drawn from the vial into the syringe by tipping the insulin bottle upside down and pulling the plunger until the proper dose is achieved. Generally, some air is injected into the vial first in order not to create a vacuum.
Insulin pens combine the medication and syringe in one convenient package. Pens come in two basic types: disposable and reusable. Disposable pens are preloaded with insulin and are discarded after the insulin cartridge is empty or the pen has been in use for 28 or 32 days (depending on insulin type). Reusable pens work with insulin cartridges that can be loaded into the pen and then tossed away once the insulin is used, leaving the pen ready for the next cartridge.
Basal and Bolus
You will need to give insulin in two different ways—as a basal dose (background insulin) and bolus doses (single use corrections and eating).
The starting doses of basal and bolus insulin are usually determined based on weight. Many factors go into determining the correct daily dose, and the dose required may change day to day based on physical activity and health. Over time, dose adjustments are often required and sometimes these doses become skewed—out of sync with what is the best insulin replacement program. Therefore, it is important to review the insulin dose program with your diabetes team to be sure the doses are correct.
Unless you go through long periods of not eating during the day, the majority of the variability in daytime blood glucose levels will be due to the bolus insulin, not the basal rate.