just to give you both sides of the coin - I think you are right to be cautious. About 6 years ago my gallbladder started playing up... it eventually got to the point of daily attacks (not fun!!). I was determined to try the flush as I had read all about it. I followed instructions to the tee. Initially the epson salts made me extremely nauseous. Then the oil mixture triggered a full on gallbladder attack. The pain was so bad my worried husband called the doctor to our home and he gave me a morphine shot. Then mid pain I began vomiting and over the next twenty four hours I alternated between blinding pain, retching and vomiting. Most of the ingredients came back up, but interestingly I did get a few "green peas" in the toilet the following morning. The gallbladder attack lasted three and a half days (previous attacks were hours) and I think it IS quite likely that a stone was stuck in the bile duct during that time.
It was obvious to me that the flush had only partially worked and that there were still many stones left, but I had been so wretchedly ill that the thought of trying again was too much to contemplete. I ended up going under the knife.
I firmly believe in the value of liver flushes, but after my own experiences I also believe that if you are already showing symptoms you are more likely to experience problems with the flush process, moreso than a person flushing as a preventative measure.
I hope this has been informative - good luck whichever way you go...