Hi there,
I know with Neocate, the small print (!!) tells you to let baby have some water as a drink as Neocate can cause constipation.
I don't have any experience with Nutramigen but as they are similiar, I'm wondering if any of the info might mention this? Otherwise, you could check if they have a website. I know Neocate have a website...
Hope this helps!
Irene