Many diabetes patients treated with insulin inject their insulin very frequently into the same areas (“favorite sites”). As a result, thickened areas can form in the subcutaneous fatty tissue at these locations. These consist of fat cells enlarged by insulin (lipohypertrophy). These injection sites not only affect appearance, but above all lead to reduced absorption of insulin and thus to decreased insulin sensitivity. If another injection site is then used (often unintentionally), this can lead to hypoglycemia in very insulin-sensitive patients.
To avoid problems at injection sites, it is necessary to inspect them frequently, preferably daily. In addition, it is helpful to develop a structured injection strategy. This works best with an “injection calendar” (Fig. SK 11).