Has anyone experienced leg/foot problems when taking metformin? I was diagnosed end November and am now taking 2 X 850 pills a day increasing to 3 by the end of this month. My legs feel heavy with calf muscles feeling strained and uncomfortable. I have numbness on the soles of my feet. I am exercising fast walking 30 mins a day and am not overweight. Didn't feel like this before taking this medication. Particularly strange feeling in the morning when I wake up. Any ideas?