Multiple Daily Injections (MDI)
With this therapy the insulin is injected at least four times a day with an insulin pen.
Two types of insulin are used:
- A long-acting insulin (“basal insulin” or “delayed-action insulin”) is injected once or twice a day in order to meet the body's basic requirements.
- A short-acting insulin (“bolus insulin”) is injected each mealtime in order to correct elevated blood glucose levels.
An insulin pen contains an insulin cartridge and a dosing device. Two different pens are used for the basal and bolus insulin.
The insulin is injected into the subcutaneous fatty tissue under the skin (subcutaneous) on the abdomen, thighs or buttocks. The pen needles used are extremely thin, so that the injection is barely noticeable. The pen needle is replaced after each injection.
Multiple Daily Injections (MDI) is the standard therapy for most people with type 1 diabetes. However, it has its limits.
Limits of MDI:
- Blood glucose levels may be too high after waking up in the morning (the “dawn phenomenon” or “daybreak phenomenon”). This is caused by changes in insulin requirements during the night, which are unable to be adequately covered with long-acting insulin.
- Long-acting insulin provides little flexibility. If the insulin requirements change suddenly, for example during physical activity/sports or in stressful situations, the body is unable to respond to these changes quick enough.
- It is difficult to manage irregular daily routines and shift work with long-acting insulin because the basic insulin requirements are constantly fluctuating.
- In children and adolescents as well as pregnant women MDI is often unable to provide satisfactory control of blood glucose levels due to hormonal fluctuations.
In these cases therapy with insulin pumps is a good alternative.
Insulin levels in the blood compared to insulin requirements...
...in people without diabetes
Release of basic insulin requirements
Meal-dependent insulin release
Bolus insulin (meal insulin)
Long-acting insulin (basal insulin)
Short-acting insulin (bolus insulin)