insulin therapy
Insulin therapy means giving insulin by injection or pump to do the job the pancreas can no longer do well enough. Insulin is the hormone that lets cells take up glucose from the blood after meals and tells the liver to stop overproducing sugar; without enough of it, blood glucose climbs to dangerous levels. Replacing it allows the body to use and store fuel normally again.
Because insulin is a protein, it would be digested if swallowed, so it is delivered under the skin. Modern regimens try to copy the healthy pancreas's two-part output: a steady background ('basal') level that controls glucose between meals and overnight, plus quick surges ('bolus') timed to each meal's carbohydrates. Engineered insulin analogs with fast or long action profiles make this basal–bolus mimicry possible.
It is life-sustaining in type 1 diabetes, where the insulin-making beta cells are destroyed, and is also used in type 2 diabetes and gestational diabetes when other measures fall short. The central hazard is hypoglycemia — too much insulin for the available glucose — so therapy is balanced against food, activity, and frequent glucose monitoring, and patients are taught to recognize and treat low blood sugar promptly.
C-peptide, released in equal amounts when the body makes its own insulin but absent from injected insulin, can be measured to tell how much insulin a patient is still producing despite therapy.