Immunotherapy with ileostomy

DX stage 4 rectal cancer due to Mets to Para aortic lymph nodes in July 2023. I’ve completed FolFoxIri, radiation to pelvis /abdomen, and finally LAR surgery with ileostomy. Unfortunately I still have minimal residual disease so I’m currently going through immunotherapy. I’m curious if anyone with an ILEOSTOMY that has gone through immunotherapy struggled with high output —> dehydration.