Description
C-peptide is a byproduct created when insulin is produced. Measuring the amount of C-peptide in blood indicates how much insulin is being produced. Generally, high C-peptide production indicates high insulin production, and vice versa. The C-peptide test is also known as the insulin C-peptide test.
C-Peptide is useful in the evaluation of pancreatic beta cell function (e.g., helping distinguish type 1 from type 2 diabetes mellitus, or monitoring patients who have received islet cell or pancreatic transplants) and for determining the source of insulin in patients with hyperinsulinemic hypoglycemia (e.g., distinguishing insulin-secreting tumors from exogenous insulin administration). It is also sometimes measured as an additional means (more resistant to hemolysis than is insulin itself) for evaluating glucose tolerance tests.
Fasting for 12 hours is recommended prior to sample collection.
