March 28, 2002
Blood Tests and Insulin Injections
Question from New York, USA:
I am a thin 30 year old diagnosed with type 1 diabetes about eight years ago, and I recently had a C-peptide of 0.2. I had the feeling that I was producing insulin because sometimes my blood sugar would go down even though I took very little or no insulin, and my Lantus dose seems low. Another thing I noticed is that taking certain kinds of medication lowers my blood sugar a great deal. What does the fact I have a C-peptide level of 0.2 mean? Aside from simple test error, is there some other way that I could have a positive C-peptide result and not actually be producing insulin? What is happening? Is there some way to maximize this residual insulin production? Any drugs or even experimental treatments that would allow me to enhance my insulin production and rely less on injections?
It would be very helpful to have had a glucose level at the same time the C-peptide was drawn. That way you could measure evaluate whether the C-peptide was appropriate for the given level of glucose. Without it, all I can say is, unless your glucose level was low, a C-peptide of 0.2 attests to the idea that you would have type 1 diabetes. Long-term insulin secretion is lost in patients with type 1 diabetes. It has not be found to be effective to give potent immunosuppressant medications to preserve what very little insulin secretion is left.