Can my baby switch between enfamil, similac, nestle's, and other formulas without any bad effects?

Probably: If your baby is doing well with one of these formulas, then in general it is recommended to stick with that one. However, if that's not possible, there will probably not be any major problems from switching as long as the baby accepts the new formula.

Caution: Baby formula is not the same as paper clips. Each has mandatory minimums of various nutrients, but your baby may process one better than another.Repeated switching is a set up for such problems as indigestion,constipation, vomiting, etc. It is best to find one your kid handles well and stay on it.