Can metformin cause high blood sugar? No, it can’t. Diabetes drug metformin acts by decreasing production of glucose in the liver, decreasing glucose absorption, and diabetes medication metformin increasing glucose uptake into skeletal muscle. Can you take metformin with insulin? Yes, you can. But why would you? If you have symptoms of type 2 diabete s and ready to use insulin, you are much better off going onn intensive diabetes management.