Best vitamins I have EVER had - pre or post op? Nutrametrix!!!!! I swear by them. It is a powder you mix with water. After the mixture stops fizzing, you sip it till it's gone. AND - its isotonic, only other thing that is isotonic is an IV. It doesn't go through the digestive process. I used to ALWAYS have to eat with a multivitamin or else I threw up. Never once have I had to eat with nutrametrix. Because it is isotonic you only have to wait 10-30 min. Before you can eat. No, I don't sell Nutrametrix, lol. My endocrinologist put me this years ago. I loved how good it made me feel also. They are more expensive than some, but comparable to bariatric advantage costs, I think. I will take Nutrametrix multivitamin and calcium at whatever the cost to me - it's been THAT worth it.