Dd is only 8 weeks old but is showing signs of CMPA and has been prescribed nutramigen by the doctor. She's been on it for a few days and seems to be able to get it down ok (I've heard of some babies refusing it completely due to the smell and taste) but she vomits a lot of it back up again. I'm worried about her losing weight. She must be hungry as nothing is staying down for long. I know there are other options but I feel like I need to give it a fair try before switching as it's bound to cause some unsettled behaviour - it's a change to her body. But how long do I leave it before worrying? It's awful seeing her like this.