Question

i have a plan and design lab to do and i need help
-your grandfather has to do a barium metal test to help locate and diagnose a stomach ulcer. he is hesitant to swallow the suspension of barium sulphate because barium compounds are poisonous. however, the doctor told him that although barium compounds are toxic, barium can be safely used in the body. suggest a hypothesis for the doctor's statement and design an experiment to test your hypothesis .

i know it has to do with the solubility of barium sulphate. it is insoluble and i think i should carry out a solubility test but .HELP!!!