How long does metformin take to get out your system. I have to have a gtt done, my surgeon requested I stop taking it to see if I am diabetic.?

DM diagnosis. No need to stop metformin. Get an a1c test not a ggt. The GGT is not recommended as a diagnostic test by the a da. A1c less than 5.7 is normal. 5.7-6.4 is pre diabetes. Above 6.5 is diabetes.