Why is insulin administered through injection?

Insulin is administered through injection primarily because it is a peptide hormone that cannot be effectively absorbed through the digestive tract. When insulin is injected, it enters the bloodstream directly, allowing for prompt and precise management of blood glucose levels.

By injecting insulin, it facilitates the uptake of glucose from the bloodstream into the cells, where it is utilized for energy. This is crucial for individuals with diabetes, as they may not produce sufficient insulin or their bodies may not respond effectively to insulin, leading to elevated blood glucose levels. Proper administration allows insulin to quickly reach its site of action, where it plays a vital role in regulating blood sugar and providing the necessary energy for cellular functions.

Insulin injections are therefore critical for ensuring that glucose is efficiently utilized by the body's tissues, which is central to diabetes management.