The epsoms salts dilates the bile ducts so that the stones and gravel can pass easily through the bile ducts and the epsoms salts also acts as a laxative to clean out the bowels first so that the way is clear for the stones and stuff to pass out of the body.
I have also done the cleanse without doing the bowel/ parasite cleanse first. Good Luck with the flush. It is not that bad.
Just think of the results and being able to eat normally again,
that should be a motivation.