Lab test · Diabetes
C-Peptide
Body's own insulin production
- Blood sample
- Fasting: 8 hours
- Report within 2 days
- Home collection
What this test is for
Body's own insulin production
When the pancreas makes insulin, it releases an equal amount of a small protein called C-peptide. Measuring C-peptide therefore shows how much insulin your own body is producing, even if you inject insulin, because injected insulin does not contain C-peptide. It helps your doctor understand the type of diabetes and how well the pancreas is still working.
Why a doctor may order it
- To help tell type 1 diabetes from type 2 diabetes when the type is unclear
- To see whether a person with diabetes is still making their own insulin
- To investigate low blood sugar episodes, including whether they come from injected insulin or the body's own insulin
- To help guide decisions about long-term diabetes treatment
How to prepare
Fasting: 8 hours without food before the sample; plain water is fine.
This test needs fasting, and the fasting time is shown on this page; plain water is allowed. If you have diabetes, especially if you use insulin or tablets that can lower blood sugar, ask your doctor how to manage your medicines while fasting and what to do if you feel shaky or unwell. Keep a sugary snack ready to have straight after the sample.
At home
- Sample
- Blood sample
- How it works
- An early morning collection is easiest while fasting. A trained collector takes a small blood sample from a vein in your arm, and you can have your usual meal straight afterwards.
- Report
- Within 2 days of collection.
What the results can mean
C-peptide is reported with the laboratory's range and is best read together with a blood sugar taken at the same time. A low C-peptide suggests the pancreas is making little insulin, as in type 1 diabetes or long-standing type 2 diabetes. A high level can be seen with insulin resistance, and reduced kidney function can also raise it because the kidneys clear C-peptide. Your doctor will interpret the result in the context of your diabetes history.
What's included
One test: C-Peptide, from one blood sample.
Related tests
- Fasting InsulinThis test measures the level of insulin in your blood after a fast.
- HOMA-IR (Insulin Resistance)HOMA-IR (Homeostatic Model Assessment of Insulin Resistance) is not a single measurement but a calculation.
- HbA1c (Glycated Haemoglobin)3-month blood sugar average৳550
- Fasting Blood Sugar (FBS)Fasting blood sugar, diabetes check৳110
- Fructosamine2 to 3-week blood sugar average৳1,390
- Random Blood Sugar (RBS)Blood sugar at any time৳150
Questions people ask
What is the difference between C-peptide and insulin tests?
Both reflect insulin made by the pancreas. C-peptide stays in the blood longer and is not affected by injected insulin, so it is often the better measure of your own insulin production.
Can C-peptide tell whether I have type 1 or type 2 diabetes?
It helps. A very low C-peptide supports type 1 diabetes, while normal or high levels are more typical of type 2. Your doctor may also use antibody tests and your history.
Does kidney disease affect C-peptide?
Yes. The kidneys clear C-peptide, so it can be higher than expected in people with reduced kidney function. Your doctor takes this into account.
How much does a C-peptide test cost in Dhaka?
With Mukti Health the price is ৳750, and the sample is collected at your home in Dhaka. You see the price again before you confirm the booking in the Mukti Health app.
Can I do the C-peptide test at home in Dhaka?
Yes. Book it in the Mukti Health app and a trained sample collector comes to your home in Dhaka to take the blood sample. You do not need to go to a laboratory.
How long does the C-peptide report take?
The report is usually ready within 2 days of the sample being collected.