This is a chicken and the egg kind of question. Which came first? If you have been taking metformin and then started NutriBlasting, it may not be the combination of the two that is causing your symptoms, rather, it may be the ingredients you are consuming. If it is the other way around or your symptoms persists for more than a couple of days, we urge you to see the doctor. While waiting to see your doctor, continue your medication as suggested by your doctor and stop NutriBlasting until you have more information why you are experiencing the problems.