From what I understand it's different for everyone, BUT I can say as one of the people that did get sick, it was not the type of sick you should worry about. About 2 hours after I drank the olive oil I woke up feeling odd. I was nauseus for about 5 minutes, vomited and in another five minutes, I felt like it never had happened and yes, the flush still worked for me with fantastic results. over 400 stones with that first flush. The second flush the same thing happened and got about 200 stones. The pain releif I experienced was so worth it though. It wasn't this terrible experience at all. it was invigorating really ... exciting even. After two flushes, I have yet to have another gallbladder attack or the other symptoms I was having. I can only say there is a reason you see people on here saying they have done numerous flushes. If it was so bad, would a person really put themselves through it again?
So take all your anxiety and tuck it away and let yourself get excited that you are about to take your own health into your own hands and do something about it, instead of suffering or popping whatever pills your doc might want to give you to relieve symptoms, but not fix the problem.