Reasons you may not be able to
have the test or why the results may not be helpful include:
Taking medicines, such as insulin, or sulfonylurea
medicines for type 2 diabetes.
Having kidney failure. Both insulin and C-peptide are
removed from the body by the kidneys. C-peptide levels may be high in a person
with kidney failure.
obese. More insulin is made in obese people and can
cause high levels of C-peptide.
What To Think About
A C-peptide test must be done at the same time
as a blood glucose test. For more information, see the topic
A person with new type 2
diabetes often has a normal or high level of C-peptide in the blood. Over time,
a person with type 2 diabetes may develop a low level of C-peptide.
To help tell the difference between type 1 and type 2 diabetes and
to help guide treatment, most doctors look at a person's age, weight, and how
long symptoms have been present. In rare cases, a C-peptide stimulation test
may be done to help tell the difference between the two types of diabetes.
During a C-peptide stimulation test, a blood sample is taken to measure
C-peptide. Then a shot of a hormone to increase blood sugar (glucagon) is given
into a vein in the arm. Another blood sample is taken. In people with type 1
diabetes, C-peptide levels will be low because the pancreas cannot make any
insulin in response to the glucagon. In people with type 2 diabetes, C-peptide
levels will be higher than the first blood test because the pancreas is making
more insulin in response to the glucagon.
Other Works Consulted
Chernecky CC, Berger BJ (2008). Laboratory Tests and Diagnostic Procedures, 5th ed. St. Louis:
Fischbach FT, Dunning MB III, eds. (2009).
Manual of Laboratory and Diagnostic Tests, 8th ed.
Philadelphia: Lippincott Williams and Wilkins.
Pagana KD, Pagana TJ (2010). Mosby’s Manual of Diagnostic and Laboratory Tests, 4th ed. St. Louis: Mosby Elsevier.
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Your level is currently
If the level is below 70 and you are experiencing symptoms such as shaking, sweating or difficulty thinking, you will need to raise the number immediately. A quick solution is to eat a few pieces of hard candy or 1 tablespoon of sugar or honey. Recheck your numbers again in 15 minutes to see if the number has gone up. If not, repeat the steps above or call your doctor.
People who experience hypoglycemia several times in a week should call their health care provider. It's important to monitor your levels each day so you can make sure your numbers are within the range. If you are pregnant always consult with your health care provider.
Congratulations on taking steps to manage your health.
However, it's important to continue to track your numbers so that you can make lifestyle changes if needed. If you are pregnant always consult with your physician.
Your level is high if this reading was taken before eating. Aim for 70-130 before meals and less than 180 two hours after meals.
Even if your number is high, it's not too late for you to take control of your health and lower your blood sugar.
One of the first steps is to monitor your levels each day. If you are pregnant always consult with your physician.
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