Substitutes for Epsom salts?

My wife would like to do another flush. First time was done without Epsom Salts and that didn't work out too well. She got some caught in her and it took a while to work them out.
She has taken Epsom Salts a long time ago and they disagreed with her violently. Since the function of the salts is to loosen things up, I was wondering of something else, like Aloe Vera , might work equally as well before she takes the olive oil.
Any thoughts?