J.P.
my daughter was a breast fed baby since birth. when she was 3 months old I needed to have a test done which required injecting dye into my blood stream and so she was going to have to be given formula for a few days until the dye left my system. She had Similac Advance and she screamed hysterical, cried for hours, had small red bumps on her skin, and clearly had a very hard time digesting. As with most formulas, depending on the child, they can be very very hard to digest. While the masses will have you think that there is nothing wrong with feeding our children formula, our children sometimes show us other wise. If you have to feed your child formula then it is a trial and error until you find one that works, and even then you may have to switch to something else after a few months. Good luck.