Terri, Metformin is a prescription drug which is used to help regulate blood sugar in diabetics. My blood glucose levels were getting quite high while I was on WW so the doc hopes this will help get them back into the safe zone. The nice side effect is that being on Metformin has helped me get into ketosis which seemed impossible the last time I tried Atkins two years ago.
BTW, I followed everyone's advice and ate lots of protein and fat and drank lots of water and this evening I am back into the pale shade of purple. Yippee.
But, you know what. All morning I was having carb cravings.

Caused by the sweet sauces in the Chinese food, no doubt. Man, am I ever sensitive to carbs! Good thing I don't go out for Chinese food too often.