What effect does the Master Cleanse have on bathroom actions? if you know what i mean?

My friend and I want to go on the Master Cleanse but unfortunately he has IBS and we are unsure as to whether or not this would effect it. Do you have any knowledge of how issues and the restroom might be effected by this cleanse. I would think it would lead to constipation if anything but maybe i am wrong. Thanks for reading this awkward question!