Which complication can arise if insulin injection sites are not rotated?

When insulin injection sites are not rotated, one of the significant complications that can arise is the development of hard painful lumps, known as lipodystrophy. This condition occurs when fat tissue under the skin changes due to repeated injections at the same site.

Using the same injection site repeatedly can lead to localized swelling, hardening, or even atrophy of the fat underneath the skin. This can affect the absorption of insulin, leading to erratic blood sugar levels, and can cause discomfort for the person receiving the injections. Rotating injection sites is essential to prevent these complications and ensure effective insulin delivery.

While other options like dry skin may be a minor concern, they do not directly relate to the practice of insulin injections. Increased appetite and shortness of breath are unrelated to the technique of insulin administration, thereby reaffirming that hard painful lumps are the most pertinent complication in this context.