That was my fear, too, but the more I read here and got informed, I realized that the chances of that happening were slim.
It also helps to know that the best thing to do if you get a stuck stone is to take more ES. I did my third flush last weekend and within 24 hrs had some pains that I assumed were GB. A dose of ES cleared it right up.
Not everyone gets nauseous, either. I have read about adding the ginger to the the potion, but haven't had the need.
My hubby is doing his first flush tonight. I don't know how excited HE is, but I cannot wait!