What difference is there in blood glucose taken from the forearm as opposed to one from the fingertips?

There can be differences that you get in your blood glucose results depending on where you test. The blood at the fingertips circulates five times faster than the arm. This can mean a big influence in test results. Changes are reflected faster at the fingers than at the arm.

One thing that might help is to rub the arm site vigorously before you test. For some people, this helps even out the results, and for some it doesn’t. If you think you are dropping your blood glucose quickly, you may want to test your finger at that point since you may miss a low otherwise. Some patients have more lag time with the arm than others. You need to assess if you fit into this category.

(Consultation done with Geoff McGarraugh, head scientist at Therasense.)

SH