I have been taking berberine for about 2 months now. I didnt have any unpleasant side effects (I used to take metformin and that will get you running to the bathroom the first week). I am however seeing a definate difference in my blood glucose. I have struggled to keep it under 100 even after a 20 - 24 hour fast. I have been eating mostly Zero Carb for years now and the blood glucose still was running 100 to 120. Taking this berberine has made a big difference. I noticed the difference right about a month in and it is continuing to improve. I started out at 500 mg 3 times a day. I haven't noticed any help with weight loss yet, I have recently been prescribed some low dose NP thyroid. Hopefully, once the thyroid gets regulated better, weight loss will follow. I never noticed ANY kind of improvement while on metformin, no help losing weight or minimizing the BG. I just now wonder what happens if I quit the berberine? I tried to google that question but have yet to really get any kind of answer.