The C-peptide looks at a marker of the body's own insulin production. It is done for: classify diabetes type.
General health information, not a diagnosis. In an emergency, call 102. Always consult a qualified health professional.
Classify diabetes type.
Often fasting. Laboratory-specific; see the reference range on your report. High or positive may mean: Insulin being produced. Low or negative may mean: Low insulin production (type 1). General information, not a diagnosis. Results must be interpreted by a qualified health worker.
A marker of the body's own insulin production.
Blood
Insulin being produced.
Low insulin production (type 1).
Reference ranges vary by lab, age and sex — always use the range printed on your own report.
Consult a doctor to interpret results — a single test does not make a diagnosis.
Uses your location once to list the nearest facilities. Nothing is stored.
What does the C-peptide measure?
A marker of the body's own insulin production.
Why is the C-peptide done?
Classify diabetes type.
Do I need to fast for the C-peptide?
Often fasting.
What does a high or positive C-peptide mean?
Insulin being produced.
What does a low or negative C-peptide mean?
Low insulin production (type 1).
What is the normal range for the C-peptide?
Laboratory-specific; see the reference range on your report.
Why is C-peptide done?
Classify diabetes type.
Do I need to prepare or fast for C-peptide?
Often fasting. Laboratory-specific; see the reference range on your report. High or positive may mean: Insulin being produced. Low or negative may mean: Low insulin production (type 1). General information, not a diagnosis. Results must be interpreted by a qualified health worker.
SI text CC BY 4.0; decoder reference data (cited per range); LOINC codes free with attribution (notice included).
Sources: SI health summary (own words); MedlinePlus Lab Tests and CDC as references