Does metformin harm to your kidneys ?

Metformin use to treat type 2 diabetc patients world wide as a first line therapy. It will reduce your blood sugar levels via 2 actions. 1.decrease glucose producttion by the liver 2.increase insulin sensivity in peripheral tissues Metformin usually well tolerated eccept few gastric side effects such as nsusea and loss of appetite. There is a popular belief among patients that metformin is harmful to kidneys. IS IT TRUE ? This is a totaly misleading myth. Actually metformin improve your blood sugar level and prevent damaging to your kidneys..but if you have already damaged kidneys due to diabetic or some other diseases , then metformin is not good. Usually physicians do not start metformin if your serum creatinin level more than 1.5 mg / dl because accumilation of metobolites can cause a seroius side effect call Lactic acidosis.. MESSAGE......... Metformin will not harm your kidneys. Actually it protect your kidneys via reducing blood sugar. But if you have alredy damaged kidneys , then metformin is not a good option.