text: questions about milk allergies and lactose intolerance? my son is 20 months old. it seems like when he has milk he either throws it up or gets diarreah. this has been happening for almost a week now. at first i thought he was sick. i don't give him cups of milk that often, he gets calcium from other foods. over the past month or more he has gotten sick requently and thinking back it seems to be after drinking milk. some told me he may have a milk allergy or be lactose intolerant. the thing is he eats cereal with milk in it, he eats cheese and yogurt, he also eats ice cream. this doesn't sound like an allergy or anything to me, maybe just a coincidence? what do you think? i could simply be a coincidence.  but you should probably bring it up with your pediatrician at your next visit.  i hope, for your son's sake, that it isn't anything serious.  i am lactose intolerant, and it's really annoying to have to check everything.  lactose intolerence can actually start as a person gets older.  i didn't have a problem with dairy until i was almost seven.  the best advice i can give you for right now is to just make sure he's getting plenty of fluids (other than milk) and don't let him have any dairy for a while.  if his symptoms persist, it's most likely just coincidental.