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"Are these C-peptide levels bad?"

ZocdocAnswersAre these C-peptide levels bad?


I almost experienced weakness of the legs, funny hearing and vision going black two weeks ago I felt like I was going to pass out they called the paramedics but my husband fed me a cookie and I came back and felt ok. I went to the doctors and had blood work done my first glucose came to 65 I went back for a follow up and had another blood test ran this time included a c peptide test Glucose: 111 C-pep- 8.7 normal range is supposed to be 0.8-3.9 All other tests came back normal He was talking about a possible tumor. I drink alot of coke zero with the artificial sweetener and drank one on the way to the doctor I also am on the mirena. Are these numbers bad? Is it high enough to be tumor related?


First of all, I am not completely sure that there is anything wrong with you, but I recommend that you schedule an appointment with an endocrinologist. Your blood glucose level of 65 is within normal limits. The value 111 his above the upper limit of normal, but probably normal if you have eaten something recently. Your doctor checked a C-peptide level, because this is standard procedure and workup when low blood glucose is suspected. The most common cause of low blood glucose is taking insulin unnecessarily. C-peptide is a byproduct of insulin metabolism and thus when it is present it means that insulin is being created inside the body. In people that take insulin unnecessarily, the C-peptide is probably low because the body did not make that insulin and therefore did not make the C-peptide. The fact that your C-peptide is high obviously means that you did take any extra insulin and might mean that your body is creating too much. There is a type of tumor called an insulinoma which is quite rare, but create excess insulin abnormally. This is a very specialized problem and thus, I would suggest that you schedule a point with an endocrinologist. The two of you can discuss your lab work and cope with a plan to arrive at a diagnosis.

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