my son taking nan also, if there is no prob, don't change it.. for the heat rash, try let ur baby wear sleeveless clothes, my boy had it too.. so I will also wipe him on and off to prevent the heat rash to appear and apply lotion to it to help it subside.. jia you
if she's ok with nan then probably good to just stick to it and not change. how is similac and enfamil better or not? if baby doesn't have diarrhoea or other allergy reactions then she's ok. for her heat rash u may want to consult a paediatrician