I give up, I surrender, metformin has gotten the better of me. I am type 2 diabetic. The doctor put me on met ten weeks ago hoping to get me off insulin(insulin was working fine to keep my glucose down, he just thought it would be more convenient for me to take tablets). I was taking extended release and taking it with meals but the vomiting and diarrhea goes on all day and just won't stop. In fact it gets worse. I gradually reduced the dosage(with his permission) from four tablets a day to one. Didn't make a bit of difference, one is as bad as four. I would rather take insulin than live like this. How long does it stay in your system -- I want to start living again! I was not overweight at the time of diagnosis. I was, and still am, underweight.