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Also known as: Insulin C-peptide
Related tests: Insulin, Glucose

At a Glance

Why Get Tested?

To monitor insulin production by the beta cells in the pancreas and to help determine the cause of hypoglycaemia (low blood sugar)

When to Get Tested?

If you haveĀ diabetes mellitus and your doctor wants to see if you are producing any of your own insulin, if you are thought to be insulin resistant (when your body does not respond properly to insulin), or to help establish if it is time to add insulin injections to your current treatment. Your doctor also may request a C-peptide blood test if you have an episode of low blood sugar, called hypoglycaemia.

Sample Required?

A blood sampleĀ taken from a vein in your arm and sometimes a 24-hour urine sample is taken

Test Preparation Needed?

Fasting for 8 to 10 hours before blood testing is usually required.