C-peptide is the product of the breakdown of proinsulin into insulin and C-peptide, which is produced in the beta cells of the pancreas. Its secretion occurs in equal amounts with insulin, but C-peptide has no biological activity, and that is why its determination is a valuable diagnostic marker of beta-cell function.

Advantages of C-peptide determination:

• Unlike insulin, C-peptide is not destroyed in the liver but is excreted by the kidneys, which allows for a more accurate assessment of the patient's own insulin secretion.
• Its level does not depend on the introduction of insulin from the outside, which makes the analysis informative even during insulin therapy.
• The results are not distorted in the presence of antibodies to insulin.

Indications for use:

• Differential diagnosis of type 1 and type 2 diabetes
• Diagnosis of the causes of hypoglycemic states
• Detection and control of insulinoma, including postoperative monitoring
• Assessment of beta-cell function: during remission of diabetes in children/adolescents, on insulin therapy, in the presence of antibodies to insulin
• Deciding whether to prescribe insulin if oral therapy is ineffective
• Assessment of insulin secretion in liver disease or after pancreatectomy

Preparation for the test:

• 8 hours before sampling, refrain from eating, exclude fatty foods
• You can drink clean water

Biological material: venous blood

Time frame: 28 hours