Hi I Have 11 Week Old Twins Who Vomit Quite

Hi i have 11 week old twins who vomit quite a bit. Ive been to their dr with them at least once a week for a month and they suggested pedialyte for 12 hours straight and then a 50/50 mixture of pedialite and formula for 12 hours then fo back to plain formula as long as they have held all that down. But i just read on the pedialite page not to mix the 2 together. What are your thoughts?