ya know, this is a matter of personal preference. it depends who you talk to.
i didn't do a parasite cleanse first. i did do a few Bowel Cleanses (blessed herbs) in order to clean out my colon some, just to make room for the toxic junk that was going to come out of my liver/gb during a flush. i didn't feel that it would be right to dump all those stones and old junky waste into an already dirty drainage pipe. i'm very glad i did the Colon Cleanse first.
i keep up with the Colon Cleanses - colonics after each flush, and also herbal colon cleanses. i think it would be disastrous (for me) not to keep cleaning your bowel while going through the Liver Flush process.