High C-peptide: what it means
A C-peptide result above the normal range is considered high. Here is what a raised C-peptide can point to, and when it is worth discussing with a doctor.
Reference range: Fasting 0.5–2.0 ng/mL; rises with carbohydrate intake. Interpreted alongside glucose.
Understand your full resultWhat a high C-peptide can mean
- Type 2 diabetes (early/mid) — insulin resistance drives compensatory hypersecretion.
- Insulinoma — pancreatic beta-cell tumour; very high C-peptide despite hypoglycaemia.
- Sulfonylurea overuse — these drugs stimulate endogenous insulin; differential vs insulinoma.
- Cushing's syndrome, acromegaly — counter-regulatory hormone excess drives insulin secretion.
When to discuss with a doctor
C-peptide is ordered when the type of diabetes is unclear (adult-onset that doesn't behave like type-2, lean patient on insulin who 'might not need it'), or to investigate hypoglycaemia (insulinoma vs factitious insulin use). It's not part of routine diabetes monitoring — HbA1c handles that. Mediora.AI shows C-peptide against glucose so the pattern (preserved vs absent insulin reserve) is visible; the diabetes-type decision is endocrinology.
Conditions this can relate to
Keep reading
One value is a snapshot. Upload the full test to see every marker explained together.
Upload your test - freeMediora.AI is informational - interpretation, not a diagnosis. A single out-of-range value is common and often benign; always discuss decisions with your doctor.