Going to the doctor this week. It's an opportunity to see what my supplement levels are at.

Should I stop taking my supplements in advance of the test (in order to get an accurate reading)? If so, how long before?

In addition to the usual blood and urine work, I will ask him to test for:

Uric Acid
B6
B12
Vit D
Magnesium

Anything else? B1 perhaps?

Thanks.

Yes, I would stop them at least 3 days prior to the testing.

The test results should be higher than normally expected however, because you have used them for a while.

B12 will be higher than if you never took any. But it should not be falsely elevated beyond what your current level is, if you stop 3 days prior.

B6 can linger for quite a while, and typically shows higher when tested when you have been using it for a while. It is stored in muscles for a time.

Magnesium testing doesn't show much ...since only very high or very low can be attributed to "symptoms". But having a level may be useful in some ways.

Yes, get the B1 tested because there is a genetic possibility of a low situation with it.