Pediasure + diarrhea

My son has always been in the lower percentile so I thought I would try pediasure. I made him a fruit smoothie with it yesterday and that’s the only different thing I did. I woke up to him standing in his crib and he had diarrhea. I mean everywhere. I had to bathe him, strip his bed, everything. I felt so bad because he was so confused and kept saying uh oh. He’s 22 months so I figured it wouldn’t hurt to try it.

Now I’m regretting it and I feel horrible because I know it has to be that. Why would it cause diarrhea like that? I’m definitely going to stop giving it to him and I’m going to call his doctor because he also has had terrible ongoing eczema since turning 12 months and they just keep telling me to put cera ve on it and while I do, it’ll go away and then come back and I have a feeling he has a couple food intolerances. He never wanted whole milk. I had to nurse him until 18 months because he wouldn’t take milk. So I am guessing it’s a dairy allergy or intolerance. Won’t eat cheese either. Yogurt is the only thing he will eat consistently without issue.