Why is insulin not given orally but is injected into the body?

Dear Student,

Insulin is a peptide hormone that is naturally produced by our pancreas to regulate the level of glucose in the blood. It doesn't allow to glucose levels to increase. If insulin is not produced in optimum amount or is not produced completely, as happens in diabetes mellitus, insulin needs to be administered from outside to supplement the body.

This hormone is injected subcutaneously ( subcutaneous tissue),? i.e. under the skin into the fat layer, which has few blood vessels. This mode of injection allows slower release and sustained rate of absorption. If insulin is injected into the blood , suddenly, the blood glucose levels will drop fast leading to hypoglycemia.

Insulin is not given orally as it reaches the stomach it will get denatured by the acidic environment of the gastric juice and by the proteases of intestinal juice.

Regards