you know our stomach has an acidic pH and it is a site of protein digestion so if you will administer insulin via oral route it will be degraded once reaching into the stomach and won't teach it's Target.
Subcutaneous or infusion mode of it's administration makes it reach it's target in an active form.
hope this helps!
A Doctor advised a patient for an insulin injection as the patient suffered from Diabetes. Insulin is produced from pancreas, from a specialized cell called as beta cells in Islets of Langerhans. It plays key role in sugar metabolism. Thus, the patient who was advised to take insulin injections might be suffering from high blood sugar level.
♤ Insulin plays an important role in sugar metabolism. In some patients of diabetes , insulin secretion is reduced.
♤ Insulin injection is given to such patients to compensate for reduced insulin secretion in the body and to regulate insulin in their body which causes diabetes when the level is fluctuated
♤ Such cases of diabetes are called Insulin Dependent Diabetes Mellitus ( IDDM ).
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