The barium swallow study… if it is the one I am thinking of… we had it done with a speech pathologist there to see if she was aspirating on her feeds. She was unfortunately. She was given bottles with the barium in them. Each bottle had a different consistentcy. They start with a waterlike one, then formula, nector, and honey which is like babyfood. After the test probably later in the afternoon, expect alot of poop that is white from the baruim. Good luck with the test..Hope you get the answers you are looking for.